ISO/DIS 10364:2026(en)

ISO/TC 61/SC 11/WG 5

Secretariat: JISC

Date: 2026-01-07

Structural adhesives — Determination of the pot life and working life of multi-component adhesives

© ISO 2026

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of the requester.

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Contents

Foreword vii

1 Scope 1

2 Normative references 1

3 Terms and definitions 1

4 Significance and use 2

5 Sampling 4

6 Method 1 — Pot life - Determination from the change in apparent viscosity 4

6.1 Materials 4

6.1.1 Solvent 4

6.1.2 Cleaning wipes 4

6.2 Apparatus 4

6.2.1 General 4

6.2.2 Rotational viscometer 4

6.2.3 Temperature control device 4

6.2.4 Balance 4

6.2.5 Cup 5

6.2.6 Spatula 5

6.2.7 Dual asymmetric centrifuge 5

6.2.8 Dispensing gun 5

6.2.9 Static mixer tip 5

6.2.10 Stopwatch 5

6.3 Procedure 5

6.4 Test report 7

7 Method 2 — Pot life - Determination from the change in extrusion rate 7

7.1 Materials 7

7.1.1 Solvent 7

7.1.2 Cleaning wipes 7

7.2 Apparatus 8

7.2.1 General 8

7.2.2 Temperature control device 8

7.2.3 Balance 8

7.2.4 Disposable plastic cartridges 8

7.2.5 Stopwatch 8

7.2.6 Stirrer 8

7.2.7 Extrusion nozzle 8

7.2.8 Extrusion gun 8

7.2.9 Dual asymmetric centrifuge (optional) 8

7.2.10 Dispensing gun 9

7.2.11 Static mixer tip 9

7.2.12 Shim 9

7.2.13 Aluminium foil dish 9

7.1 Procedure 9

7.2 Test report 10

8 Method 3 — Pot life - Determination from the reaction temperature 11

8.1 Materials 11

8.1.1 Solvent 11

8.1.2 Cleaning wipes 11

8.2 Apparatus 11

8.2.1 General 11

8.2.2 Thermometer 11

8.2.3 Temperature control device 11

8.2.4 Balance 11

8.2.5 Cup 12

8.2.6 Spatula 12

8.2.7 Dual asymmetric centrifuge 12

8.2.8 Dispensing gun 12

8.2.9 Static mixer tip 12

8.2.10 Stopwatch 12

8.3 Procedure 12

8.4 Test report 13

9 Method 4 — Pot life - Determination by means of a drying recorder 14

9.1 Materials 14

9.1.1 Solvent 14

9.1.2 Cleaning wipes 14

9.2 Apparatus 14

9.2.1 General 14

9.2.2 Temperature control device 14

9.2.3 Drying recorder 15

9.2.4 Gauge 15

9.2.5 Stopwatch 15

9.2.6 Flat glass ledge 15

9.2.7 Balance 15

9.2.8 Cup 15

9.2.9 Spatula 15

9.2.10 Dual asymmetric centrifuge 15

9.2.11 Dispensing gun 16

9.2.12 Static mixer tip 16

9.2.13 Film applicator 16

9.2.14 10 g weight 16

9.3 Procedure 16

9.4 Test report 17

10 Method 5 — Pot life - Determination by measuring the “snap time” 18

10.1 Materials 18

10.1.1 Solvent 18

10.1.2 Cleaning wipes 18

10.2 Apparatus 18

10.2.1 General 18

10.2.2 Temperature control device 18

10.2.3 Balance 19

10.2.4 Cup 19

10.2.5 Spatula 19

10.2.6 Dual asymmetric centrifuge 19

10.2.7 Dispensing gun 19

10.2.8 Static mixer tip 19

10.2.9 Stopwatch 19

10.3 Procedure 20

10.4 Test report 21

11 Method 6 — Pot life - Determination from the change in wetting properties 22

11.1 Materials 22

11.1.1 Solvent 22

11.1.2 Cleaning wipes 22

11.2 Apparatus 22

11.2.1 General 22

11.2.2 Temperature control device 23

11.2.3 Balance 23

11.2.4 Cup 23

11.2.5 Spatula 23

11.2.6 Dual asymmetric centrifuge 23

11.2.7 Dispensing gun 23

11.2.8 Static mixer tip 24

11.2.9 Single component cartridge 24

11.2.10 Applicator 24

11.2.11 Test panel 24

11.2.12 Wooden spatula 24

11.2.13 Stopwatch 24

11.2.14 Gauge 24

11.3 Procedure 24

11.4 Test report 27

12 Method 7 — Pot life - Determination from the change in tensile lap share strength 28

12.1 Materials 28

12.1.1 Solvent 28

12.1.2 Cleaning wipes 28

12.2 Apparatus 28

12.2.1 Gerneral 28

12.2.2 Temperature control device 28

12.2.3 Adherends 28

12.2.4 Spacer 28

12.2.5 Balance 29

12.2.6 Cup 29

12.2.7 Spatula 29

12.2.8 Dual asymmetric centrifuge 29

12.2.9 Dispensing gun 29

12.2.10 Static mixer tip 29

12.2.11 Stopwatch 29

12.2.12 Tensile testing machine 29

12.3 Procedure 30

12.4 Test report 31

13 Method 8 — Working life - Determination from the change in tensile lap share strength 32

13.1 Materials 32

13.1.1 Solvent 32

13.1.2 Cleaning wipes 32

13.2 Apparatus 33

13.2.1 Gerneral 33

13.2.2 Temperature control device 33

13.2.3 Adherends 33

13.2.4 Spacer 33

13.2.5 Balance 33

13.2.6 Cup 33

13.2.7 Spatula 33

13.2.8 Dual asymmetric centrifuge 34

13.2.9 Dispensing gun 34

13.2.10 Static mixer tip 34

13.2.11 Stopwatch 34

13.2.12 Tensile testing machine 34

13.3 Procedure 34

13.4 Test report 36

Bibliography 38

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

ISO draws attention to the possibility that the implementation of this document may involve the use of (a) patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s) which may be required to implement this document. However, implementers are cautioned that this may not represent the latest information, which may be obtained from the patent database available at www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.

Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISO's adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 11, Products in collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC 193, Adhesives, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).

This fifth edition cancels and replaces the fourth edition (ISO 10364:2024), which has been technically revised.

The main changes are as follows:

— The structure of the standard has been changed making it more user friendly. Each of the methods is now described in a separate clause containing the list of materials and equipment, a description of the procedure and the specific requirements for the content of the test report;

— The somewhat misleading information on the relevance of the respective methods of some methods has been adjusted;

— The option of mixing the adhesive components using a dual asymmetric centrifuge has been added;

— Clause 3.1 pot life: definition adjusted;

— Clause 3.2 working life: definition adjusted;

— Clause 11: Method 6: Pot life - Determination from the change in wetting properties has been added;

— Clause 12: Method 7: Pot life - Determination – from the change in tensile lap shear strength has been added;

— Clause 13: Method 8: Working life - Determination – from the change in tensile lap shear strength has been added.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

Structural adhesives — Determination of the pot life and working life of multi-component adhesives

SAFETY STATEMENT — Persons using this document should be familiar with normal laboratory practice, if applicable. This document does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to determine any regulatory requirements prior to use.

This document specifies methods for determining the pot life of multi-part adhesives, in order to be able to determine whether the pot life conforms to the minimum specified working life required for a specific bonding process or to determine the reactivity of a multi-component adhesive as part of an incoming or outgoing goods inspection.

The different methods described in this document to measure the property do not necessarily provide identical results.

The test methods described are suitable for assessing all multi–part adhesives, and especially epoxy based and polyurethane based adhesives, but they may not suitable for some acrylic-based adhesives.

NOTE 1 Some of the methods described in this document can also be suitable for determination of working life of one-part adhesives that react to humidity (e.g. PUR prepolymers).

NOTE 2 This document can also be used for assessing non-structural adhesives.

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

ISO 472, Plastics — Vocabulary

ISO 2555, Plastics — Resins in the liquid state or as emulsions or dispersions — Determination of apparent viscosity using a single cylinder type rotational viscometer method

ISO 3219‑2, Rheology — Part 2: General principles of rotational and oscillatory rheometry

ISO 15605, Adhesives — Sampling

ISO 4587, Adhesives — Determination of tensile lap-shear strength of rigid-to-rigid bonded assemblies

ISO 10365, Adhesives — Designation of main failure patterns

For the purposes of this document, the terms and definitions given in ISO 472 and the following apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https://www.iso.org/obp

— IEC Electropedia: available at https://www.electropedia.org/

3.1

pot life

maximum time period, starting with the first contact of the components of a multi-component adhesive, within which the rheological properties of the adhesive allow it to be dispensed to the adherend and sufficiently wet both this and the adherends applied during joining; the steps to be carried out within the pot life are: dosing and mixing of the components, dispensing of the mixed adhesive to the adherend, joining and clamping the adherends

Note 1 to entry: The pot life varies with volume (more precisely with the surface to volume ratio of the tested adhesive sample), the temperature of the mixed adhesive and the ambient temperature.

3.2

working life

pot life plus the time interval within which the adherends can still be repositioned slightly by moving them parallel to each other after joining without adversely affecting the bond

Note 1 to entry: The pot life varies with volume (more precisely with the surface to volume ratio of the tested adhesive sample), the temperature of the mixed adhesive and the ambient temperature.

3.3

open time

maximum permissible time interval between the start of the application of the adhesive to the adherends and the completion of the joining process

[SOURCE: EN 923: proposed revised wording]

The pot life as well as the working life of a multi-component adhesive are important adhesive properties with regard to its processing. Even if the information about the pot life in the technical data sheets was originally intended to give the adhesive user an indication of how long an adhesive can be processed after mixing the individual components, methods have now also been established that allow to check the adhesive’s reactivity as part of quality assurance, whether in outgoing or incoming goods inspection, but do not necessarily allow conclusions to be drawn about suitability for a specific bonding process.

The methods for measuring pot life described in this document do not give identical results. While some of these methods are primarily intended as a method for quality assurance in the context of incoming and outgoing goods inspection, others allow statements to be made as to whether the pot life of an adhesive is meeting the requirements of a specific bonding process. It should be expressly noted at this point that due to the numerous test conditions that influence the result of the pot life measurement, a comparison of the values is only possible if all the parameters listed in the sections on the test reports are taken into account.

Even if the test methods described are in principle applicable to all multi–part adhesive chemistries, especially epoxy based and polyurethane based adhesives the suitability of individual methods may be limited e.g. by the length of the pot life or the rheological behaviour of the respective adhesive.

— Method 1: Pot life - Determination from the change in apparent viscosity, (see 6);

— Method 2: Pot life - Determination from the change in extrusion rate, (see 7);

— Method 3: Pot life - Determination from the reaction temperature, (see 8);

— Method 4: Pot life - Determination by means of a drying recorder, (see 9);

— Method 5: Pot life - Determination by measuring the “snap time” , (see 10);

— Method 6: Pot life - Determination from the change in wetting properties, (see 11);

— Method 7: Pot life - Determination from the change in tensile lap shear strength, (see 12);

— Method 8: Working life - Determination from the change in tensile lap shear strength, (see 13).

In method 1, the pot life is determined from the increase in viscosity of the adhesive as it cures. This method is applicable to adhesives having a pot live of at least 5 min. It is particularly suitable as a quality test in the outgoing goods or incoming goods inspection. The informative value with regard to the suitability of a multi-component adhesive for a specific bonding process is limited to the influence of the curing reaction on the pumpability of the adhesive.

In method 2, the pot life is determined from the decrease in the mass of the mixed adhesive extruded under standard conditions in one unit of time. This method is applicable to adhesives having a pot live of at least 5 min. It is particularly suitable as a quality test in the outgoing goods or incoming goods inspection. The informative value with regard to the suitability of a multi-component adhesive for a specific bonding process is limited to the influence of the curing reaction on the pumpability of the adhesive.

In method 3, the pot life is determined as the time required for the mixed adhesive to reach a certain temperature, the so-called critical temperature, due to the exothermic nature of the curing reaction. This method is in principle applicable to all multi-part systems. It is particularly suitable as a quality test in the outgoing or incoming goods inspection, but it is almost not suitable to check whether or not the pot life of an adhesives is suitable for a certain bonding process.

In method 4, the pot life is determined by the time within the adhesive film still closes after a weighted needle is pulled through known as film formation time. In addition, the film drying time can be determined as the time from which the needle lifts out of the adhesive and continues gliding on the film surface without leaving any marks. This method is limited to low-viscosity, self-leveling multi-part adhesives and allows certain conclusions to be drawn about the suitability of the adhesive for a particular process.

NOTE This method is also applicable to one-component moisture-curing adhesives for determination of the open time.

In method 5, the pot life is determined as the change in string building, called snap time. This method is suitable for multi-part silicone, polyurethane, epoxy and methylmethacrylate adhesives. Other multi-part adhesives showing a similar flow behaviour and can be tested by snap time as well. The method allows certain conclusions to be drawn about the suitability of the adhesive for a particular process.

In method 6, the change in the ability of the adhesive to wet a surface is used to determine the pot life. The advantage of this method is that the pot life can be determined on a bead that is similar to the bead geometry intended for the bonding process in question. This method can be used for all multi-part adhesives that can be applied as a bead. It allows reliable statements to be made as to whether the pot life of a multi-component adhesive is suitable for a particular bonding process.

In method 7, the pot life is determined using tensile lap shear test specimens in accordance with ISO 4587. For this purpose, tensile lap shear test specimens are produced, whereby the joining is performed immediately as well as at different times after mixing the multi-component adhesive. The pot life is the maximum time after which no significant reduction in tensile tap shear strength or a significant increase in the proportion of adhesive failure is observed. This method, which is suitable for almost all multi-part adhesives, allows very reliable statements about whether the pot life of a multi-component adhesive is suitable for a particular bonding process due to the possibility of adapting the test conditions largely to the respective bonding process. The disadvantage of this method is the time required to carry out the determination.

In method 8, the working life is determined using tensile lap shear test specimens in accordance with ISO 4587. For this purpose, tensile shear test specimens are produced, whereby the joining is performed within the pot life of the multi-component adhesive. Immediately after joining and at different times after the joining, the adherends are moved parallel to the bonding surface to simulate an adjustment of the alignment. After complete curing, destructive testing is carried out. The working life is the maximum time after which no significant reduction in tensile tap shear strength or a significant increase in the proportion of adhesive failure is observed. This method, which is suitable for almost all multi-part adhesives, allows very reliable statements about whether the working life of a multi-component adhesive is suitable for a particular bonding process due to the possibility of adapting the test conditions largely to the respective bonding process. The disadvantage of this method is the time required to carry out the determination.

Each part of the multi-part adhesive shall be sampled, prepared and examined in accordance with ISO 15605. For each of the eight methods described in chapters 6 to 13, a sample quantity shall be taken that allows at least three tests to be carried out.

Suitable for removing residues of the adhesive being tested from the devices used.

NOTE Acetone usually has a good cleaning effect on polyurethane or MMA adhesives, epoxy adhesives can often be removed well with isopropanol.

Resistant to the solvent used, preferably disposable.

This section lists and describes the equipment required to determine the pot life using this method. The necessary dosing and mixing of the adhesive components can be carried out in different ways

— manual dosing and mixing;

— manual dosing and machine mixing;

— dosing from dual cartridge through a static mixer;

so that depending on the selected method, some of the listed items are not required. This is indicated accordingly.

Independent of the dosing and mixing method used a rotational viscosimeter that should comply with the requirements of ISO ISO 2555 or ISO 3219-2 is required.

Independent of the dosing and mixing method used a temperature control device for conditioning the adhesive components to a specific temperature is required. This can be either a water bath or a temperature control chamber, each of which being capable of maintaining the desired temperature with an accuracy of ±0,1 °C.

When using a water bath, direct contact between the adhesive components and the water of the water bath shall be avoided.

Due to the risk of contamination of the adhesive components by water, adhesives supplied in dual cartridges shall not be thermally conditioned using a water bath.

For manual dosing a balance capable of weighing up to (100 ± 0,1) g for narrow gap cylindrical, cone-plate or plate-plate measuring systems and up to (500 ± 0,1) g for infinitive gap cylindrical measuring systems is required.

Exept as if the adhesive is dispensed from a dual cartridge a cup preferably disposable, with a flat bottom and of suitable size, made of a material that is not adversely affected by the adhesive to be tested, with a wall thickness of not more than 1 mm is required. Wax-coated disposable paper cups have depending on the exotherm of the adhesive and the softening point of the wax coating a potential influence on the test result.

For manual mixing a spatula made of a material which does not react with the adhesive under test having at least one square (not rounded) end. Although disposable wooden spatulas can be used, stainless steel spatulas are preferred, especially for highly viscous adhesives due to their greater mechanical stability and for polyurethane adhesives to prevent moisture from the wood reacting with the isocyanate component. Commonly available wooden spatulas have rounded ends. To avoid insufficient mixing in the corners between the bottom and the wall of the cup, the rounded end shall be cut-off before use.

A spatula is not required if mixing of the components is performed either using a dual asymmetric centrifuge (6.2.7) or if the adhesive is delivered in a dual cartridge and applied using a dispensing gun (6.2.8) via a static mixer (6.2.9).

As an alternative to manual mixing the use of a dual asymmetric centrifuge allowing rotation speeds of up to approx. 3 000 rpm^[1], together with a closable beaker suitable for the device (in accordance with the requirements provided in 6.2.5) with a volume adapted to the required amount of adhesive, provides typically excellent mixing results with short mixing times.

NOTE 1 The shear forces that occur during mixing cause the adhesive mixture to heat up, which affects the pot life value determined.

If the adhesive is dispensed from a dual cartridge a suitable dispensing gun together with a suitable static mixer tip (6.2.9) is required. Manual, compressed air and battery-operated guns are suitable.

If the adhesive is dispensed from a dual cartridge a static mixer tip specified and approved for the respective adhesive shall be used.

With an uncertainty of measurement < ±1 s.

In principle, each rotational viscometer (6.2.2), equipped either with a cylindrical, a cone-plate, or a plate-plate measuring system, capable of handling the expected viscosities can be used. It shall be differentiated between cylindrical measuring systems with a narrow gap between the two coaxial surfaces of which one is rotating and the other remains static and those, like Brookfield having a large, so to say, infinite gap.

Narrow gap cylindrical viscometer require typically just approximately 10 ml and cone-plate and plate-plate viscometer an even smaller amount of adhesive. Such systems are suitable for adhesives showing a relative short pot life. In case the adhesive contains mineral fillers, either cylindrical or a plate-plate system shall be used. The use of cone-plate systems shall be limited to un-filled adhesives.

Cylindrical viscometers with a large gap, such as Brookfield systems, require a significantly larger amount of adhesive, typically 300 ml and are therefore not suitable for fast-reacting adhesives or adhesives showing a high exotherm. On the other hand, they can be used for both filled and unfilled adhesives.

The use of a disposable measuring system, especially a disposable static measuring chamber, is recommended to avoid time-consuming cleaning operation.

The components of the adhesive are separately condition to an uniform agreed temperature using the water bath or conditioning chamber (6.2.3). When using a water bath the adhesive shall not come into direct contact with the water.

NOTE 1 (23 ± 2) °C is commonly used.

The time necessary for conditioning depends on the type and mass of adhesive concerned and shall be determined for each adhesive before starting the test.

The sample of mixed adhesive required for the measurement can be prepared from the conditioned individual components of the multi-component adhesive in different ways:

— Weighing using a suitable balance (6.2.4) the individual components into a cup (6.2.5) of appropriate size observing the mixing ratio specified by the manufacturer for the particular adhesive. The amount of mixture depends on the amount required by the specific viscometer used. In all cases, a sufficient amount to allow a fast and easy transfer into the measuring system shall be prepared.

Start the stopwatch (6.2.10) and mix the test sample with the square (not rounded) end of the spatula (6.2.6) for (60 ± 10) s. Take care that the areas in the angle between the side and bottom of the cup are well mixed and avoid mixing-in of air.

Instead of manual mixing using a spatula, a laboratory dual asymmetric centrifuge mixing system (6.2.7) can be used. Consider the material warming that occurs as a result of the mixing process.

Upon completion of mixing, immediately transfer the mixed adhesive into the measuring system avoiding incorporation of air bubbles and start measuring the viscosity of the adhesive using the selected viscometer (6.2.2).

— In case the adhesive is available in a dual cartridge it can be directly dispensed from the dual cartridge through a defined and approved static mixer (6.2.9) to the measuring system of the selected viscometer using a suitable dispensing gun (6.2.8).

Before dispensing the adhesive to the measuring system, the common steps of levelling the cartridge plunger before attaching the mixer and discarding at least one mixer volume shall be performed.

Start the stopwatch (6.2.10) at the time when dispense is started.

Start measuring the viscosity of the adhesive using the selected viscometer (6.2.2).

Depending on the expected open time and the viscometer used, readings should be taken at appropriate intervals, or the viscosity-time graph is recorded. Typically, the pot life of the adhesive is specified as the time difference between start of mixing and the time when a specific viscosity, e.g. 100 000 mPas, is reached.

It is also possible to specify the end point as a fixed agreed multiple, e.g. the double of the starting viscosity. In this case, the first viscosity measurement after mixing is taken as the starting point.

NOTE 2 Differences in the time required for mixing and transferring the adhesive into the measuring system will have, depending on the kinetics of the crosslinking reaction, a more or less effect on the test result.

The number of measurements, as well as the degree of shear during mixing and during the measurement itself, might have an influence on the viscosity and hence, the pot life. Therefore, it is recommended that the measurement interval, as well as the mixing speed and the rotational speed of the viscometer, shall be selected to suit the adhesive under test.

The test report shall include the following information:

a) a reference to this document, i.e. ISO 10364, and the reference number of the method used;

b) the pot life determined for each individual measurement in hours, minutes and/or seconds as appropriate as well as the median in case 3 – 5 samples have been tested respectively the mean value together with the standard deviation in case 6 or more samples have been tested;

c) total amount of mixed adhesive;

d) specified mixing ratio;

e) actual mixing ratio;

f) mixing process used;

g) if a dual asymmetric centrifuge mixing system was used, mixing time and speed in rpm;

h) if dispensed from a dual cartridge type and size as well as description of mixer tip used (type, diameter and number of mixing elements);

i) amount of adhesive transferred into the measuring system;

j) measuring system used including gap width if a narrow-gap cylindrical, cone-plate or plate-plate measuring systems is used;

k) either shear rate in s-1 or shear speed, in rpm;

l) continuous or interrupted shear;

m) if interrupted, shear time intervals between and duration of shear periods;

n) time intervals between the individual readings;

o) conditioning temperature;

p) ambient temperature during the measurement;

q) any relevant observations, such as setting, discoloration, separation, caking or gelling, which might have influenced the usability of the adhesive;

r) any other factors which might have influenced the result;

s) date of the test.

Suitable for removing residues of the adhesive being tested from the devices used.

NOTE Acetone usually has a good cleaning effect on polyurethane or MMA adhesives, epoxy adhesives can often be removed well with isopropanol.

Resistant to the solvent used, preferably disposable.

This section lists and describes the equipment required to determine the pot life using this method. The necessary dosing and mixing of the adhesive components can be carried out in different ways

— manual dosing and mixing;

— manual dosing and machine mixing;

— dosing from dual cartridge through a static mixer;

so that depending on the selected method, some of the listed items are not required. This is indicated accordingly.

Independent of the dosing and mixing method used a temperature control device for conditioning the adhesive components to a specific temperature is required. This can be either a water bath or a temperature control chamber, each of which being capable of maintaining the desired temperature with an accuracy of ±0,1 °C.

When using a water bath, direct contact between the adhesive components and the water of the water bath shall be avoided.

Due to the risk of contamination of the adhesive components by water, adhesives supplied in dual cartridges shall not be thermally conditioned using a water bath.

For manual dosing a balance capable of weighing up to (500 ± 0,1) g.

Standard size of 310 ml, internal diameter 47 mm, length 210 mm, and fitted with a threaded end and supplied with a plunger, both cartridge, and plunger being made of a material which does not react with the adhesive under test.

Uncertainty of measurement < ±1 s.

Electrically or pneumatically powered, speed should be regulated between 0 min⁻¹ and 1 000 min⁻¹, equipped with a rigid, helical stirrer blade made of a material which does not react with the adhesive under test.

Made of material which does not react with the adhesive under test, capable of being screwed onto the end fitting of the cartridge (7.2.4). The diameter of the nozzle's extrusion orifice shall be suitable for dispensing the mixed adhesive. An orifice diameter of 3 mm shall be used.

Powered by compressed air, suitable for use with the cartridge (7.2.4).

As an alternative to mixing the components inside the disposable plastic cartridge (7.2.4) with the stirrer (7.2.6) a dual asymmetric centrifuge allowing rotation speeds of up to approx. 3 000 rpm^[2], together with a closable beaker suitable for the device with a volume adapted to the required amount of adhesive may be used. In this case the mixed adhesive has to be transferred from the clisable beaker used into the cartridge (7.2.4) avoiding entrapped air. Such mixer provides typically excellent mixing results with short mixing times.

NOTE 1 The shear forces that occur during mixing cause the adhesive mixture to heat up, which affects the pot life value determined.

If the adhesive is delivered in a dual cartridge it can be directly dispensed by the use of a suitable dispensing gun together with a suitable static mixer tip (7.2.11). Manual, compressed air and battery-operated guns are suitable.

Specified and approved for the respective adhesive.

Approx. 10 cm long piece of fishing line with a diameter of 0,5 - 1,0 mm.

Diameter of 70 mm to 100 mm.

The components of the adhesive are separately conditioned to an uniform agreed temperature using the temperature control device (7.2.2).

NOTE 1 (23 ± 2) °C is commonly used.

The time necessary for conditioning depends on the type and mass of adhesive concerned and shall be determined for each adhesive before starting the test.

The sample of mixed adhesive (comonly 200 g of mixed adhesive are used, any other quantity shall be recorded and given in the test report) required for the measurement can be prepared from the conditioned individual components of the multi-component adhesive in different ways:

— Weigh using a suitable balance (7.2.3) the individual components directly into the cartridge (7.2.4) used for determining the extrusion rate, start the first stopwatch (7.2.5) and mix them thoroughly in situ using a suitable stirrer (7.2.6) operating at a speed of (600 ± 100) min−1 for (60 ± 10) s.

Take care that the areas in the angle between the side and bottom of the cartridge are well mixed and avoid mixing-in of air.

As quickly as is practical, remove the stirrer from the cartridge. Insert a plunger and press it down to the adhesive’s level. Use a shim to allow air to escape. Before inserting the piston into the cartridge, make sure that the cavities created when pulling out the stirrer are filled again. This process can be accelerated, especially if the adhesive does not show sufficient flow properties for this, by lightly tapping the cartridge held vertically on a support. Remove the seal from the threaded end fitting of the cartridge, screw on the extrusion nozzle (7.2.7), and place the cartridge in the extrusion gun (7.2.8).

— Instead of mixing the component inside the cartridge (7.2.4) by the suitable stirrer (7.2.6) mixing can be performed using, a laboratory dual asymmetric centrifuge mixing system (7.2.9) followed by transferring the mixed adhesive into the cartridge (7.2.4) avoiding entrapping air. The first stopwatch (7.2.5) is started as the mixing process in the laboratory dual asymmetric centrifuge mixing system is started. Consider the material warming that occurs as a result of the mixing process.

— In case the adhesive is available in a dual cartridge it can be directly dispensed from the dual cartridge through a defined and approved static mixer (7.2.11) into the cartridge (7.2.4) using a suitable dispensing gun (7.2.10). Before dispensing the adhesive to the measuring system, the common steps of levelling the cartridge plunger before attaching the mixer and discarding at least one mixer volume shall be performed.

Start the first stopwatch (7.2.5) at the time when filling the cartridge (7.2.4) with the mixed adhesive starts.

Avoid entrapping air during the filling process by keeping the orifice of the static mixer always below the surface level of the adhesive.

Immediately after either the adhesive has been mixed inside the cartridge (7.2.4) or the mixed adhesive has been transferred to the cartridge (7.2.4) insert a plunger and press it down to the adhesive’s level. Use a shim (7.2.12) to allow air to escape as the plunger pressed down to the adhesive, remove the seal from the threaded end of the cartridge, screw on the extrusion nozzle (7.2.7), and place the cartridge (7.2.4.) in the extrusion gun (7.2.8).

As quickly as is practical, establish the agreed upon extrusion pressure.

In order to remove any air trapped and potentially present unmixed material that might be retained in the end fitting during stirring extrude about 50 ml of adhesive rapidly, through the nozzle, into a weighed (used the balance 7.2.3) aluminium-foil dish (7.2.13).

Start the second stopwatch (7.2.5) and extrude the freshly mixed adhesive at the specified pressure for the specified length of time. Reweigh the dish and record the amount of adhesive extruded.

Repeat this procedure at appropriate time intervals until the quantity of adhesive extruded under the specified conditions has fallen to an agreed level.

The time that has elapsed up to the moment when this occurs is the pot life. If the agreed extrusion rate has already been underrun at the last measurement, the pot life can be estimated from the graph of the extrusion rate plotted against time. This shall then be noted in the test report.

The test report shall include the following information:

a) a reference to this document, i.e. ISO 10364, and the reference number of the method used;

b) the pot life determined for each individual measurement in hours, minutes and/or seconds as appropriate as well as the median in case 3 – 5 samples have been tested respectively the mean value together with the standard deviation in case 6 or more samples have been tested;

c) time dependent extrusion rate in g/min;

d) total amount of mixed adhesive;

e) specified mixing ratio;

f) actual mixing ratio;

g) mixing process used;

h) if dispensed from a dual cartridge type and size as well as description of mixer tip used (type, diameter and number of mixing elements);

i) if a dual asymmetric centrifuge mixing system was used, mixing time and speed in rpm;

j) amount of adhesive transferred into the measuring cartridge;

k) extrusion pressure;

l) duration of the individual extrusion processes;

m) time interval between the individual extrusion processes;

n) conditioning temperature;

o) ambient temperature during the measurement;

p) any relevant observations, such as setting, discoloration, separation, caking or gelling, which might have influenced the usability of the adhesive;

q) any other factors which might have influenced the result;

r) date of the test.

Suitable for removing residues of the adhesive being tested from the devices used.

NOTE Acetone usually has a good cleaning effect on polyurethane or MMA adhesives, epoxy adhesives can often be removed well with isopropanol.

Resistant to the solvent used, preferably disposable.

This section lists and describes the equipment required to determine the pot life using this method. The necessary dosing and mixing of the adhesive components can be carried out in different ways

— manual dosing and mixing;

— manual dosing and machine mixing;

— dosing from dual cartridge through a static mixer;

so that depending on the selected method, some of the listed items are not required. This is indicated accordingly.

Analogue or digital with a reading accuracy of at least ±0,1 °C.

Independent of the dosing and mixing method used a temperature control device for conditioning the adhesive components to a specific temperature is required. This can be either a water bath or a temperature control chamber, each of which being capable of maintaining the desired temperature with an accuracy of ±0,1 °C.

When using a water bath, direct contact between the adhesive components and the water of the water bath shall be avoided.

Due to the risk of contamination of the adhesive components by water, adhesives supplied in dual cartridges shall not be thermally conditioned using a water bath.

For manual dosing a balance capable of weighing up to (500 ± 0,1) g.

Exept as if the adhesive is dispensed from a dual cartridge a cup preferably disposable, with a flat bottom and of suitable size, made of a material that is not adversely affected by the adhesive to be tested, with a wall thickness of not more than 1 mm is required. Wax-coated disposable paper cups have depending on the exotherm of the adhesive and the softening point of the wax coating a potential influence on the test result.

For manual mixing a spatula made of a material which does not react with the adhesive under test having at least one square (not rounded) end. Although disposable wooden spatulas can be used, stainless steel spatulas are preferred, especially for highly viscous adhesives due to their greater mechanical stability and for polyurethane adhesives to prevent moisture from the wood reacting with the isocyanate component. Commonly available wooden spatulas have rounded ends. To avoid insufficient mixing in the corners between the bottom and the wall of the cup, the rounded end shall be cut-off before use.

As an alternative to manual mixing the use of a dual asymmetric centrifuge allowing rotation speeds of up to approx. 3 000 rpm^[3], together with a closable beaker suitable for the device (in accordance with the requirements provided in 8.2.5) with a volume adapted to the required amount of adhesive, provides typically excellent mixing results with short mixing times.

NOTE 1 The shear forces that occur during mixing cause the adhesive mixture to heat up, which affects the pot life value determined.

If the adhesive is delivered in a dual cartridge it can be directly dispensed by the use of a suitable dispensing gun together with a suitable static mixer tip (8.2.9) is required. Manual, compressed air and battery-operated guns are suitable.

If the adhesive is dispensed from a dual cartridge a static mixer tip specified and approved for the respective adhesive shall be used.

Uncertainty of measurement < ±1 s.

Before the measurement starts, the critical temperature (e.g. 40 °C) shall be specified, taking into account the heat generated by the chemical cure reaction and the processing behaviour of the adhesive system under test.

The components of the adhesive are separately condition to an uniform agreed temperature using the temperature control device (8.2.3).

NOTE 1 (23 ± 2) °C is commonly used.

The time necessary for conditioning depends on the type and mass of adhesive concerned and shall be determined for each adhesive before starting the test.

The amount of mixture depends on the dimension of the cup (8.2.5) used. In any case, the quantity shall be sufficient to ensure that the thermometer (8.2.2) immersed in the adhesive for the measurement is adequately surrounded at all sides by the mixed adhesive. On the other hand, the quantity should be kept as low as possible to avoid inappropriate acceleration of the curing reaction due to the heat of reaction generated.

For adhesives with pot lives of more than 10 min, the preferred amount of mixture is 100 g. For adhesives with pot lives less than 10 min, the preferred amount of mixture is 20 g. However, other quantities may also be used.

The sample of mixed adhesive required for the measurement can be prepared from the conditioned individual components of the multi-component adhesive in different ways:

— Weigh using a suitable balance (8.2.4) the individual components into a cup (8.2.5) of appropriate size observing the mixing ratio specified by the manufacturer for the particular adhesive.

Start the stopwatch (8.2.10) and mix the test sample with the square (not rounded) end of the spatula (8.2.6) for (60 ± 10) s. Take care that the areas in the angle between the side and bottom of the cup are well mixed and avoid mixing-in of air.

Instead of manual mixing using a spatula, a laboratory dual asymmetric centrifuge mixing system (8.2.7) can be used. Consider the material warming that occurs as a result of the mixing process.

— In case the adhesive is available in a dual cartridge it can be directly dispensed from the dual cartridge through a defined and approved static mixer (8.2.9) into the cup (8.2.5) placed on the balance (8.2.4) using a suitable dispensing gun (8.2.8).

Before dispensing into the cup, the common steps of levelling the cartridge plungers before attaching the static mixer tip and discarding at least one mixer volume shall be performed.

Start the stopwatch (8.2.10) at the time when dispense is started.

Upon completion of mixing, immediately position the thermometer (8.2.2) in the middle of the adhesive in a way that it is adequately surrounded at all sides by the mixed adhesive.

Record the temperature and the time elapsed since the start of the mixing process at regular intervals adapted to the expected pot life.

Stop taking measurements when the critical temperature is reached. Take the time between the beginning of mixing and the point when the critical temperature is reached as the pot life.

For adhedives that do not reach the critical temperature, this shall be noted in the report and the time until the maximum temperature is reached shall be reported as the pot life.

The test report shall include the following information:

a) a reference to this document, i.e. ISO 10364, and the reference number of the method used;

b) Indication of whether the pre-defined critical temperature or the maximum temperature reached was used as a criterion;

c) the pot life determined for each individual measurement in hours, minutes and/or seconds as appropriate as well as the median in case 3 – 5 samples have been tested respectively the mean value together with the standard deviation in case 6 or more samples have been tested;

d) dimensions of the cup used;

e) time dependent temperature in °C;

f) amount of mixed adhesive used for the test;

g) specified mixing ratio;

h) actual mixing ratio;

i) mixing process used;

j) if a dual asymmetric centrifuge mixing system was used, mixing time and speed in rpm;

k) if dispensed from a dual cartridge type and size as well as description of mixer tip used (type, diameter and number of mixing elements);

l) time interval between the individual temperature readings;

m) conditioning temperature;

n) ambient temperature during the measurement;

o) any relevant observations, such as setting, discoloration, separation, caking or gelling, which might have influenced the usability of the adhesive;

p) any other factors which might have influenced the result;

q) date of the test.

Suitable for removing residues of the adhesive being tested from the devices used.

NOTE Acetone usually has a good cleaning effect on polyurethane or MMA adhesives, epoxy adhesives can often be removed well with isopropanol.

Resistant to the solvent used, preferably disposable.

This section lists and describes the equipment required to determine the pot life using this method. The necessary dosing and mixing of the adhesive components can be carried out in different ways

— manual dosing and mixing;

— manual dosing and machine mixing;

— dosing from dual cartridge through a static mixer;

so that depending on the selected method, some of the listed items are not required. This is indicated accordingly.

Independent of the dosing and mixing method used a temperature control device for conditioning the adhesive components to a specific temperature is required. This can be either a water bath or a temperature control chamber, each of which being capable of maintaining the desired temperature with an accuracy of ±0,1 °C.

When using a water bath, direct contact between the adhesive components and the water of the water bath shall be avoided.

Due to the risk of contamination of the adhesive components by water, adhesives supplied in dual cartridges shall not be thermally conditioned using a water bath.

Including several (e.g. six or 10) sample holders arranged in parallel and accompanying motor driven linear moving needle holders.

Centimetre and millimetre grading and a minimum length of 30 mm.

Uncertainty of measurement < ±1 s.

Dimensions: 300 mm × 25 mm × 3 mm.

Capable of weighing up to (100 ± 0,1) g.

Exept as if the adhesive is dispensed from a dual cartridge a cup preferably disposable, with a flat bottom and of suitable size, made of a material that is not adversely affected by the adhesive to be tested, with a wall thickness of not more than 1 mm is required. Wax-coated disposable paper cups have depending on the exotherm of the adhesive and the softening point of the wax coating a potential influence on the test result.

For manual mixing a spatula made of a material which does not react with the adhesive under test having at least one square (not rounded) end. Although disposable wooden spatulas can be used, stainless steel spatulas are preferred, especially for highly viscous adhesives due to their greater mechanical stability and for polyurethane adhesives to prevent moisture from the wood reacting with the isocyanate component. Commonly available wooden spatulas have rounded ends. To avoid insufficient mixing in the corners between the bottom and the wall of the cup, the rounded end shall be cut-off before use.

A spatula (9.2.) is not required if mixing of the components is performed either using a dual asymmetric centrifuge (9.2.10) or if the adhesive is delivered in a dual cartridge and applied using a dispensing gun (9.2.11) via a static mixer (9.2.12).

As an alternative to manual mixing the use of a dual asymmetric centrifuge allowing rotation speeds of up to approx. 3 000 rpm^[4], together with a closable beaker suitable for the device (in accordance with the requirements provided in 9.2.8) with a volume adapted to the required amount of adhesive, provides typically excellent mixing results with short mixing times.

NOTE 1 The shear forces that occur during mixing cause the adhesive mixture to heat up, which affects the pot life value determined.

If the adhesive is delivered in a dual cartridge it can be directly dispensed by the use of a suitable dispensing gun together with a suitable static mixer tip (9.2.12) is required. Manual, compressed air and battery-operated guns are suitable.

If the adhesive is dispensed from a dual cartridge a static mixer tip specified and approved for the respective adhesive shall be used.

Dimensions: gap height 250 μm, width 20 mm.

With a drilled hole for easy attaching to the needles.

The components of the adhesive are separately conditioned to an uniform agreed temperature using the temperature control device (9.2.2). When using a water bath the adhesive shall not come into direct contact with the water.

NOTE 1 (23 ± 2) °C is commonly used.

The time necessary for conditioning depends on the type and mass of adhesive concerned and shall be determined for each adhesive before starting the test.

Before the measurement starts the throughput speed of the drying recorder (9.2.3) is set using a gauge (9.2.4) and a stopwatch (9.2.5), measured and recorded. The throughput speed shall be chosen according to the adhesive's reactivity, such that at the end of the test procedure, the film is dry. For comparison measurements, always the same throughput speed shall be applied.

The flat glass ledge (9.2.6) shall be marked with a starting line between 1 cm to 3 cm apart from one end.

The sample of mixed adhesive (comonly 25 g of mixed adhesive are used, any other quantity shall be recorded and given in the test report) required for the measurement can be prepared from the conditioned individual components of the multi-component adhesive in different ways:

— Weigh using a suitable balance (9.2.7) the individual components into a cup (9.2.8) of appropriate size observing the mixing ratio specified by the manufacturer for the particular adhesive.

Start the stopwatch (9.2.5) and mix the test sample with the square (not rounded) end of the spatula (9.2.9) for (60 ± 10) s. Take care that the areas in the angle between the side and bottom of the cup are well mixed and avoid mixing-in of air.

Instead of manual mixing using a spatula, a laboratory dual asymmetric centrifuge mixing system (9.2.10) may be used. Consider the material warming that occurs as a result of the mixing process.

— In case the adhesive is available in a dual cartridge it can be directly dispensed from the dual cartridge through a defined and approved static mixer (9.2.12) using a suitable dispensing gun (9.2.11). Before dispensing into the cup, the common steps of levelling the cartridge plungers before attaching the static mixer tip and discarding at least one mixer volume shall be performed.

Place the film applicator (9.2.13) on the flat glass ledge (9.2.6) at the previously marked start line and transfer the mixed adhesive onto the film applicator (9.2.13) using the spatula (9.2.9). Drawing the film applicator the adhesive is spread to a uniform thickness of 250 μm along the whole length of the flat glass ledge (9.2.6).

Where the adhesive is supplied in a double cartridge, the adhesive can be dispensed directly into film applicator (9.2.13). To apply the correct amount of adhesive, the flat glass ledge (9.2.6) should be placed on the tared balance (9.2.7).

Likewise, a one-part adhesive, which is reactive to humidity, can be dispensed directly into film applicator (9.2.13) and levelled as described.

The flat glass ledge (9.2.6) with the adhesive film applied is put immediately into the sample receiver of the drying recorder (9.2.3) and the needle is positioned on the starting line by moving the needle holder. The needle shall be positioned at the correct height, such that it just touches the surface of the adhesive.

The needle is loaded with the 10 g weight (9.2.14) by placing the hole in the weight on the tip of the needle. Immediately afterwards the feed is started .

After completion of the test, the starting point and the end point of the film formation time shall be determined through the trace of the needle. Both the starting point and end point of the trace are measured from the starting line using the gauge. The film formation time and the film drying time are calculated using Formula (1) and Formula (2) and the results shall be given in the test report.

(1)

(2)

where

t_f is the film formation time, in min;

t_d is the film drying time, in min;

t_o is the time from start of mixing to start of the drying recorder;

s_f is the covered distance until formation point, in mm;

s_d is the covered distance until film drying point, in mm;

is the feed rate of the needle mm/min.

For highly viscous or thixotropic adhesives, the pin may leave a consistent trace at the beginning of the test. Thus, there is no need to report the film formation time; this shall be stated in the test report.

The test report shall include the following information:

a) a reference to this document, i.e. ISO 10364, and the reference number of the method used;

b) the film formation and the film drying time determined for each individual measurement in hours, minutes and/or seconds as appropriate as well as the median in case 3 – 5 samples have been tested respectively the mean value together with the standard deviation in case 6 or more samples have been tested;

c) total amount of mixed adhesive;

d) specified mixing ratio;

e) actual mixing ratio;

f) mixing process used;

g) if a dual asymmetric centrifuge mixing system was used, mixing time and speed in rpm;

h) if dispensed from a dual cartridge type and size as well as description of mixer tip used (type, diameter and number of mixing elements);

i) thickness, width and length of the adhesive film applied to the glass ledge;

j) feed rate of the needle;

k) conditioning temperature;

l) ambient temperature during the measurement;

m) any relevant observations, such as setting, discoloration, separation, caking or gelling, which might have influenced the usability of the adhesive;

n) any other factors which might have influenced the result;

o) date of the test.

Suitable for removing residues of the adhesive being tested from the devices used.

NOTE Acetone usually has a good cleaning effect on polyurethane or MMA adhesives, epoxy adhesives can often be removed well with isopropanol.

Resistant to the solvent used, preferably disposable.

This section lists and describes the equipment required to determine the pot life using this method. The necessary dosing and mixing of the adhesive components can be carried out in different ways

— manual dosing and mixing;

— manual dosing and machine mixing;

— dosing from dual cartridge through a static mixer;

so that depending on the selected method, some of the listed items are not required. This is indicated accordingly.

Independent of the dosing and mixing method used a temperature control device for conditioning the adhesive components to a specific temperature is required. This can be either a water bath or a temperature control chamber, each of which being capable of maintaining the desired temperature with an accuracy of ±0,1 °C.

When using a water bath, direct contact between the adhesive components and the water of the water bath shall be avoided.

Due to the risk of contamination of the adhesive components by water, adhesives supplied in dual cartridges shall not be thermally conditioned using a water bath.

Capable of weighing up to (100 ± 0,1) g.

Exept as if the adhesive is dispensed from a dual cartridge a cup preferably disposable, with a flat bottom and of suitable size, made of a material that is not adversely affected by the adhesive to be tested, with a wall thickness of not more than 1 mm is required. Wax-coated disposable paper cups have depending on the exotherm of the adhesive and the softening point of the wax coating a potential influence on the test result.

For manual mixing a spatula made of a material which does not react with the adhesive under test having at least one square (not rounded) end. Although disposable wooden spatulas can be used, stainless steel spatulas are preferred, especially for highly viscous adhesives due to their greater mechanical stability and for polyurethane adhesives to prevent moisture from the wood reacting with the isocyanate component. Commonly available wooden spatulas have rounded ends. To avoid insufficient mixing in the corners between the bottom and the wall of the cup, the rounded end shall be cut-off before use.

A spatula (10.2.5) is not required if mixing of the components is performed either using a dual asymmetric centrifuge (10.2.6) or if the adhesive is delivered in a dual cartridge and applied using a dispensing gun (10.2.7) via a static mixer (10.2.8).

As an alternative to manual mixing the use of a dual asymmetric centrifuge allowing rotation speeds of up to approx. 3 000 rpm^[5], together with a closable beaker suitable for the device (in accordance with the requirements provided in 6.2.4) with a volume adapted to the required amount of adhesive, provides typically excellent mixing results with short mixing times.

NOTE 1 The shear forces that occur during mixing cause the adhesive mixture to heat up, which affects the pot life value determined.

If the adhesive is delivered in a dual cartridge it can be directly dispensed by the use of a suitable dispensing gun together with a suitable static mixer tip (10.2.8) is required. Manual, compressed air and battery-operated guns are suitable.

If the adhesive is dispensed from a dual cartridge a static mixer tip specified and approved for the respective adhesive shall be used.

Uncertainty of measurement < ±1 s.

The components of the adhesive are separately condition to an uniform agreed temperature using the temperature control device (10.2.2).

NOTE 1 (23 ± 2) °C is commonly used.

The time necessary for conditioning depends on the type and mass of adhesive concerned and shall be determined for each adhesive before starting the test.

As the snap time strongly depends on material temperature, intensive machine mixing, e.g by using a Dual asymmetric centrifuge (10.2.6) may heat the adhesive and shorten snap time, compared to static mixer or stirring by hand. Always the same dosing and mixing system sdhall be used to compare snap time measurement results.

The sample of mixed adhesive required for the measurement (comonly 25 g of mixed adhesive are used, any other quantity shall be recorded and given in the test report) can be prepared from the conditioned individual components of the multi-component adhesive in different ways:

Weigh using a suitable balance (10.2.3) the individual components into a cup (10.2.4) of appropriate size observing the mixing ratio specified by the manufacturer for the particular adhesive.

Start the stopwatch (10.2.9) and mix the test sample with the square (not rounded) end of the spatula (10.2.5) for (60 ± 10) s. Take care that the areas in the angle between the side and bottom of the cup are well mixed and avoid mixing-in of air.

The spatula (10.2.5) remains in the adhesive.

Instead of manual mixing using a spatula, a laboratory dual asymmetric centrifuge mixing system (10.2.6) may be used. Consider the material warming that occurs as a result of the mixing process.

— In case the adhesive is available in a dual cartridge it can be directly dispensed from the dual cartridge through a static mixer tip (10.2.8) into the cup (10.2.4) placed on the balance (10.2.3) using a suitable dispensing gun (10.2.7).

Before dispensing into the cup, the common steps of levelling the cartridge plungers before attaching the static mixer tip and discarding at least one mixer volume shall be performed.

Start the stopwatch (10.2.9) at the time when dispense is started.

From about half of the expected pot life, the mixture is stirred briefly and vigorously with the spatula (10.2.5) at intervals of 5 minutes, with short pot lives and towards the end of the pot life at correspondingly shorter intervals, and the spatula is quickly removed from the mixture and the appearance of the adhesive is assessed with regard to the formation of adhesive threads. Return the spatula to the mixture.

If the vigorous stirring is repeated for too long or at too short intervals, especially at the beginning of the test, the build-up of mechanical strength may be disturbed resulting in a prolonged pot life .

As long as the adhesive is still dripping back into the cup when the spatula is pulled out of the mixture or shows a paste-like behaviour forming long threads as shown in Figure 1, the pot life or snap time has not yet been reached. The pot life is reached when the adhesive shows a rubbery behaviour when the spatula is pulled out and breaks off in short sections as shown in Figure 2.

Figure 1 — Material shows paste-like behaviour — Snap time not yet reached

Figure 2 — Material shows rubber-like behaviour — Snap time reached

The test report shall include the following information:

a) a reference to this document, i.e. ISO 10364, and the reference number of the method used;

b) the film formation and the film drying time determined for each individual measurement in hours, minutes and/or seconds as appropriate as well as the median in case 3 – 5 samples have been tested respectively the mean value together with the standard deviation in case 6 or more samples have been tested;

c) all details necessary for complete identification of the adhesive, including type, source, the manufacturer's code number, form and batch number and/or date of manufacture;

d) details of the mixing and dispensing process (i.e. mix ratio, manual mix, mix by electrical stirrer including mixing time, static mixer tip (including information on the mixer used (type, diameter, number of mixing elements), dispensing equipment);

e) total amount of mixed adhesive;

f) specified mixing ratio;

g) actual mixing ratio;

h) mixing process used;

i) dimensions and material of the cup used;

j) if a dual asymmetric centrifuge mixing system was used, mixing time and speed in rpm;

k) if dispensed from a dual cartridge type and size as well as description of mixer tip used (type, diameter and number of mixing elements);

l) conditioning temperature;

m) ambient temperature during the measurement;

n) any relevant observations, such as setting, discoloration, separation, caking or gelling, which might have influenced the usability of the adhesive;

o) any other factors which might have influenced the result;

p) date of the test.

Sauitable for removing residues of the adhesive being tested from the devices used.

NOTE Acetone usually has a good cleaning effect on polyurethane or MMA adhesives, epoxy adhesives can often be removed well with isopropanol.

Resistant to the solvent used, preferably disposable.

This section lists and describes the equipment required to determine the pot life using this method. The necessary dosing and mixing of the adhesive components can be carried out in different ways

— manual dosing and mixing;

— manual dosing and machine mixing;

— dosing from dual cartridge through a static mixer;

so that depending on the selected method, some of the listed items are not required. This is indicated accordingly.

Independent of the dosing and mixing method used a temperature control device for conditioning the adhesive components to a specific temperature is required. This can be either a water bath or a temperature control chamber, each of which being capable of maintaining the desired temperature with an accuracy of ±0,1 °C.

When using a water bath, direct contact between the adhesive components and the water of the water bath shall be avoided.

Due to the risk of contamination of the adhesive components by water, adhesives supplied in dual cartridges shall not be thermally conditioned using a water bath.

For manual dosing a balance capable of weighing up to (100 ± 0,1) g.

Exept as if the adhesive is dispensed from a dual cartridge a cup preferably disposable, with a flat bottom and of suitable size, made of a material that is not adversely affected by the adhesive to be tested, with a wall thickness of not more than 1 mm is required. Wax-coated disposable paper cups have depending on the exotherm of the adhesive and the softening point of the wax coating a potential influence on the test result.

For manual mixing a spatula made of a material which does not react with the adhesive under test having at least one square (not rounded) end. Although disposable wooden spatulas can be used, stainless steel spatulas are preferred, especially for highly viscous adhesives due to their greater mechanical stability and for polyurethane adhesives to prevent moisture from the wood reacting with the isocyanate component. Commonly available wooden spatulas have rounded ends. To avoid insufficient mixing in the corners between the bottom and the wall of the cup, the rounded end shall be cut-off before use.

A spatula is not required if mixing of the components is performed either using a dual asymmetric centrifuge (11.2.6) or if the adhesive is delivered in a dual cartridge and applied using a dispensing gun (11.2.7) via a static mixer (11.2.8).

As an alternative to manual mixing the use of a dual asymmetric centrifuge allowing rotation speeds of up to approx. 3 000 rpm^[6], together with a closable beaker suitable for the device (in accordance with the requirements provided in 11.2.4) with a volume adapted to the required amount of adhesive, provides typically excellent mixing results with short mixing times.

NOTE 1 The shear forces that occur during mixing cause the adhesive mixture to heat up, which affects the pot life value determined.

If the adhesive is delivered in a dual cartridge it can be directly dispensed by the use of a suitable dispensing gun together with a suitable static mixer tip (11.2.8) is required. Manual, compressed air and battery-operated guns are suitable.

If the adhesive is dispensed from a dual cartridge a static mixer tip specified and approved for the respective adhesive shall be used.

With a suitable dispense gun, empty for dispensing the mixed adhesive. Only required if the adhesive is not dispensed from a dual cartridge.

Required for shaping the bead with the agreed width and height in case the adhesive is dispensed from the cup (11.2.4) used for mixing the components that means not dispensed from a dual cartridge or a single component cartridge (11.2.9).

Sufficiently flat to allow the application of a bead of at least 30 cm in length. Ideally made from the same or a material with a similar thermal conductivity of the material the adherends used with the designated bonding process are made from. For comparison testing of different adhesive a cardboard panel should be used.

Dimensions: 20 – 25 mm wide.

Uncertainty of measurement < ±1 s.

Centimetre and millimetre grading and a minimum length of 300 mm.

The components of the adhesive are separately condition to an uniform agreed temperature using the temperature control device (11.2.2).

NOTE 1 (23 ± 2) °C is commonly used.

The time necessary for conditioning depends on the type and mass of adhesive concerned and shall be determined for each adhesive before starting the test.

The sample of mixed adhesive (comonly 50 g to 100 g of mixed adhesive are used, any other quantity shall be recorded and given in the test report) required for the measurement can be prepared from the conditioned individual components of the multi-component adhesive in different ways. Whenever possible dispensing from a dual cartridge (or when appropriate using the metering equipment) is the preferred method.

NOTE 2 Since the pot life depends on the material temperature, this temperature has an influence on the determined pot life. Intensive mechanical mixing e.g. by using a dual assymetric centrifuge (11.2.6) leads to increased material warming compared to mixing by hand or using a static mixer, and thus to a shorter pot life.

— If the adhesive is available in a dual cartridge, use a suitable dispensing gun (11.2.7) to apply a bead at least 30 cm long having the agreed width and height onto the test panel (11.2.11) through the static mixer (11.2.8).

To check the suitability of an adhesive with regard to its pot life for a specific process, it is recommended to use the bead geometry (width and height) as intended in the process.

Before dispensing the adhesive the common steps of levelling the cartridge plungers before attaching the static mixer tip and discarding at least one mixer volume shall be performed.

Start the stopwatch (11.2.13) at the time when dispensing of the bead was completed.

— In case the adhesive is not available in a dual cartridge use a suitable balance (11.2.3) to weigh the individual components into a cup (11.2.4) of appropriate size observing the mixing ratio specified by the manufacturer for the particular adhesive. The quantity of adhesive should allow the production of a bead of at least 30 cm in length and the agreed width and height.

To check the suitability of an adhesive with regard to its pot life for a specific process, it is recommended to use the bead geometry (width and height) as intended in the process.

Start the stopwatch (11.2.13) and mix the adhesive with the square (not rounded) end of the spatula (11.2.5) for (60 ± 10) s. Take care that the areas in the angle between the side and bottom of the cup are well mixed and avoid mixing-in of air.

Instead of manual mixing using a spatula, a laboratory dual asymmetric centrifuge mixing system (11.2.6) can be used. Consider the material warming that occurs as a result of the mixing process.

Use the mixed adhesive to apply a bead having the agreed upon dimensions to the test panel (11.2.11).

This can be realised, for example, by spreading the mixed adhesive on the test panel (11.2.11) using an appropriate applicator (11.2.10) or by first transferring it to a commercially available single-component cartridge (11.2.9) and applying it to the test panel (11.2.11) using a suitable dispense gun.

Mixing and transferring the mixture into the disposable standard single component cartridge should not take longer then 50 % of the expected pot life.

To check the suitability of an adhesive with regard to its pot life for a specific process, it is recommended to use the bead geometry (width and height) as intended in the process.

After about half to two thirds of the expected pot life, a wooden spatula (11.2.12) is carefully pressed into the adhesive bead under light pressure (Figure 3) and removed again. Check whether the wooden spatula has been wetted by the adhesive, i.e. adhesive has been transferred to the surface of the wooden spatula (11.2.12) indicating that the pot life has not yet been reached. Note the time at which the wooden spatula was pressed in the bead.

Using new wooden spatulas (11.2.12), this process is repeated every 2 minutes in an untested section of the adhesive bead. This is done by moving slowly towards the end of the bead. If the bead is applied directly from double cartridge, this minimises the error resulting from the time required to apply the bead, as the timer was started at the end of the dispensing process. For fast-curing adhesives or towards the end of the expected pot life, the intervals should be reduced to increase the accuracy of the measurement.

As long as adhesive is transferred to the entire surface of the wooden spatula pressed into the adhesive bead (Figure 4), the pot life has not yet been reached.

If adhesive is only transferred to part of the surface of the wooden spatula (Figure 5), the pot life has almost been reached. The time interval until the next measurement shall be reduced.

If no adhesive has been transferred to the wooden spatula (Figure 6), the pot life has already been reached.

The time at which adhesive was last transferred to the wooden spatula is recorded as the pot life.

NOTE 2 The accuracy of the method is affected by the length of the pot life (the shorter the pot life, the better the accuracy) and the mechanical properties, in particular the hardness of the cured adhesive (the harder the adhesive, the better the accuracy).

Figure 3 — Pressing the wooden spatula into the adhesive bead and removing it

Figure 4 — Pot life not jet reached

Figure 5 — Pot life nearly reached

Figure 6 — Pot life reached

The test report shall include the following information:

a) a reference to this document, i.e. ISO 10364, and the reference number of the method used;

b) the pot life determined;

c) the intermediate results and the time intervals between measurements;

NOTE One option for documenting the results is a photo taken at the end of the test showing the spatulas on which the respective time of the test is noted (see Figure 7).

Figure 7 — Example for documentation of pot life measurement according to method 6

d) all details necessary for complete identification of the adhesive, including type, source, the manufacturer's code number, form and batch number and/or date of manufacture;

e) material of the panel the adhesive has been dispensed to;

f) geometry of the dispensed bead (i.e. length, width and hight);

g) total amount of mixed adhesive;

h) specified mixing ratio;

i) actual mixing ratio;

j) mixing process used;

k) dimensions and material of the cup used for mixing;

l) if a dual asymmetric centrifuge mixing system was used, mixing time and speed in rpm;

m) if dispensed from a dual cartridge type and size as well as description of mixer tip used (type, diameter and number of mixing elements);

n) temperature at which the adhesive was conditioned for application;

o) ambient temperature during the test;

p) any relevant observations, such as setting, discoloration, separation, caking or gelling, which might have influenced the usability of the adhesive;

q) any other factors which might have influenced the result;

r) date of the test.

Suitable for removing residues of the adhesive being tested from the devices used.

NOTE Acetone usually has a good cleaning effect on polyurethane or MMA adhesives, epoxy adhesives can often be removed well with isopropanol.

Resistant to the solvent used, preferably disposable.

This section lists and describes the equipment required to determine the pot life using this method. The necessary dosing and mixing of the adhesive components can be carried out in different ways

— manual dosing and mixing;

— manual dosing and machine mixing;

— dosing from dual cartridge through a static mixer;

so that depending on the selected method, some of the listed items are not required. This is indicated accordingly.

Independent of the dosing and mixing method used a temperature control device for conditioning the adhesive components to a specific temperature is required. This can be either a water bath or a temperature control chamber, each of which being capable of maintaining the desired temperature with an accuracy of ±0,1 °C.

When using a water bath, direct contact between the adhesive components and the water of the water bath shall be avoided.

Due to the risk of contamination of the adhesive components by water, adhesives supplied in dual cartridges shall not be thermally conditioned using a water bath.

Dimensions according to ISO 4587, which correspond to the adherends in the respective bonding process in terms of material and surface quality, including surface treatment.

Required to adjust bondline thickness. Wire spacers and small glass beads can be positioned in the adhesive layer when relatively thin adhesive layers (typically < 0,5 mm) are required. If wire spacers are used, the wire shall be aligned parallel to the direction of the load applied during the test in order to minimise the influence of the wire on the test result. If thicker adhesive layers are required, it is recommended that PTFE spacers of the appropriate thickness are positioned at the overlap ends outside the adhesive surface.

For manual dosing a balance capable of weighing up to (100 ± 0,1) g.

Exept as if the adhesive is dispensed from a dual cartridge a cup preferably disposable, with a flat bottom and of suitable size, made of a material that is not adversely affected by the adhesive to be tested, with a wall thickness of not more than 1 mm is required. Wax-coated disposable paper cups have depending on the exotherm of the adhesive and the softening point of the wax coating a potential influence on the test result.

For manual mixing a spatula made of a material which does not react with the adhesive under test having at least one square (not rounded) end. Although disposable wooden spatulas can be used, stainless steel spatulas are preferred, especially for highly viscous adhesives due to their greater mechanical stability and for polyurethane adhesives to prevent moisture from the wood reacting with the isocyanate component. Commonly available wooden spatulas have rounded ends. To avoid insufficient mixing in the corners between the bottom and the wall of the cup, the rounded end shall be cut-off before use.

A spatula is not required if mixing of the components is performed either using a dual asymmetric centrifuge (12.2.8) or if the adhesive is delivered in a dual cartridge and applied using a dispensing gun (12.2.9) via a static mixer (12.2.10).

As an alternative to manual mixing the use of a dual asymmetric centrifuge allowing rotation speeds of up to approx. 3 000 rpm^[7], together with a closable beaker suitable for the device (in accordance with the requirements provided in 12.2.6) with a volume adapted to the required amount of adhesive, provides typically excellent mixing results with short mixing times.

NOTE 1 The shear forces that occur during mixing cause the adhesive mixture to heat up, which affects the pot life value determined.

If the adhesive is delivered in a dual cartridge it can be directly dispensed by the use of a suitable dispensing gun together with a suitable static mixer tip (12.2.10) is required. Manual, compressed air and battery-operated guns are suitable..

If the adhesive is dispensed from a dual cartridge a static mixer tip specified and approved for the respective adhesive shall be used.

Uncertainty of measurement < ±1 s.

Equipped with a load cell that the fracture of the specimen should occure at a force between 10 % and 80 % of the full load capacity. The response time of the machine shall be short enough that the force applied at the time of break can be measured accurately. The recorded force shall not deviate from the actual force applied by more than 1 %.

The machine shall be equipped with a suitable pair of grips allowing to compensate the misalignment caused by the overlap and the bondline between the two adherends of the specimen. The specimen grips and their mountings shall be designed so that the longitudinal axis of the specimen coincides with the direction of the applied force through the centre line of the specimen grips.

Grips that operate by bolting through the adherends should not be used since such grips can lead to undesirable stress peeks which further result in premature failure of the adherend.

The components of the adhesive are separately condition to an uniform agreed temperature using the temperature control device (12.2.2).

NOTE 1 (23 ± 2) °C is commonly used.

The time necessary for conditioning depends on the type and mass of adhesive concerned and shall be determined for each adhesive before starting the test.

The sample of mixed adhesive required for the measurement can be prepared from the conditioned individual components of the multi-component adhesive in different ways:

— If the adhesive is available in a dual cartridge, use a suitable dispensing gun (12.2.9) to apply the adhesive from the double cartridge onto the adherends (12.2.3) through the static mixer (12.2.10).

Before dispensing the adhesive the common steps of levelling the cartridge plungers before attaching the static mixer tip and discarding at least one mixer volume shall be performed.

Start the stopwatch (12.2.11) at the time when starting applying the adhesive to the adherends (12.2.3).

— In case the adhesive is not available in a dual cartridge use a suitable balance (12.2.5) to weigh the individual components into a cup (12.2.6) of appropriate size observing the mixing ratio specified by the manufacturer for the particular adhesive. The quantity of adhesive mixed shall be sufficient to prepare the required number of tensile shear test specimens. However, it shall be ensured that only as much adhesive is mixed per mixing process as can be applied to the adherends within half the expected pot life.

Start the stopwatch (12.2.11) and mix the adhesive with the square (not rounded) end of the spatula (12.2.7) for (60 ± 10) s. Take care that the areas in the angle between the side and bottom of the cup are well mixed and avoid mixing-in of air.

Instead of manual mixing using a spatula, a laboratory dual asymmetric centrifuge mixing system (12.2.8) can be used. Consider the material warming that occurs as a result of the mixing process.

Apply the mixed adhesive to one of the adherends (12.2.3) to prepare the tensile lap shear specimens in accordance to ISO 4587.

Place the spacers (12.2.4) to ensure the specified thickness of the adhesive joint.

In order to completely dispense with spacers, it is also possible to use special joining devices that by design ensure the specified adhesive layer thickness.

For a first set of at least 3 test specimens, joining with the second adherend takes place as soon as possible after mixing. For further series, again of minimum 3 test specimens each joining is performed according to staggered time periods, whereby the time intervals between the series become shorter as approaching the expected pot life. The last series should be joined well after the end of the expected pot life.

The test specimens are cured according to the adhesive manufacturer’s recommendation or according to the cure conditions used for the specific bonding process.

Destructive testing of samples cured at room temperature (commonly at 23 °C ± 2 °C) is typically carried out after 7 days at the earliest.

Specimens cured at elevated temperature should be conditioned at room temperature (commonly 23 °C ± 2 °C) for at least 24 h before destructive testing.

The destructive test is carried out at a specified speed in accordance with ISO 4587 using the tensile testing machine (12.2.12). The highest force during rupture is recorded as the breaking force for each specimen.

For each test specimen, the highest force during fracture is recorded as the breaking force (together with the type of failure determined in accordance with ISO 10365.

The lap shear strength is calculated according to Formula (3)

(3)

where

is the lap shear strength in N/mm² or MPa;

is the strength at break, in N;

is the overlap length in mm;

is the width of the bonded area in mm;

A is the bond area in mm².

For each series of three to five specimens the lap shear strength is expressed as the median, for series with more than five specimens as the mean value including the standard deviation.

The pot life is the maximum time elapsed between mixing the adhesive and joining the second adherend the specimens do not show a significant reduction in the tap shear strength or a significant increase in the proportion of adhesive failure.

The test report shall include the following information:

a) a reference to this document, i.e. ISO 10364, and the reference number of the method used;

b) the pot life determined as the time elapsed between mixing the adhesive and joining the second adherend after which no significant reduction in the tensile tap shear strength or a significant increase in the proportion of adhesive failure is observed;

c) all details necessary for complete identification of the adhesive, including type, source, the manufacturer's code number, form and batch number and/or date of manufacture;

d) material of the lap shear test;

e) geometry of the dispensed bead (i.e. length, width and hight);

f) total amount of mixed adhesive;

g) specified mixing ratio;

h) actual mixing ratio;

i) mixing process used;

j) dimensions and material of the cup used for mixing;

k) if a dual asymmetric centrifuge mixing system was used, mixing time and speed in rpm;

l) if dispensed from a dual cartridge type and size as well as description of mixer tip used (type, diameter and number of mixing elements);

m) temperature at which the adhesive was conditioned for application;

n) ambient temperature during the test;

o) temperature at which the adhesive was conditioned for application;

p) ambient temperature during preparation of the lap shear test specimens;

q) material and surface preparation of the adherends;

r) a complete description of the specimens, including;

— dimensions of the adherends (length, width, thickness);

— overlap length;

— bondline thickness;

— type of spacers used;

— whether the adherends were prepared individually or from panels, if the adherends were prepared from panels the number of panels used, the procedure and conditions used to cut out the adherends and the number of individual specimens tested per series;

s) temperature during destructive the test;

t) the speed of destructive testing;

u) for each individual test specimen;

— the mean, respectively average breaking force;

— the mean, respectively average lap shear strength;

— the mean, respectively average failure mode according to ISO 10365;

v) for each individual test series;

— the mean, respectively average breaking force;

— the mean, respectively average lap shear strength;

— the mean, respectively average failure mode according to ISO 10365;

w) any relevant observations, such as setting, discoloration, separation, caking or gelling, which might have influenced the usability of the adhesive;

x) any other factors which might have influenced the result;

y) date of the test.

Suitable for removing residues of the adhesive being tested from the devices used.

NOTE Acetone usually has a good cleaning effect on polyurethane or MMA adhesives, epoxy adhesives can often be removed well with isopropanol.

Resistant to the solvent used, preferably disposable.

This section lists and describes the equipment required to determine the pot life using this method. The necessary dosing and mixing of the adhesive components can be carried out in different ways

— manual dosing and mixing;

— manual dosing and machine mixing;

— dosing from dual cartridge through a static mixer;

so that depending on the selected method, some of the listed items are not required. This is indicated accordingly.

Independent of the dosing and mixing method used a temperature control device for conditioning the adhesive components to a specific temperature is required. This can be either a water bath or a temperature control chamber, each of which being capable of maintaining the desired temperature with an accuracy of ±0,1 °C.

When using a water bath, direct contact between the adhesive components and the water of the water bath shall be avoided.

Due to the risk of contamination of the adhesive components by water, adhesives supplied in dual cartridges shall not be thermally conditioned using a water bath.

Dimensions according to ISO 4587, which correspond to the adherends in the respective bonding process in terms of material and surface quality, including surface treatment.

Used to adjust bondline thickness. Wire spacers and small glass beads can be positioned in the adhesive layer when relatively thin adhesive layers (typically < 0,5 mm) are required. If wire spacers are used, the wire shall be aligned parallel to the direction of the load applied during the test in order to minimise the influence of the wire on the test result. If thicker adhesive layers are required, it is recommended that PTFE spacers of the appropriate thickness are positioned at the overlap ends outside the adhesive surface.

For manual dosing a balance capable of weighing up to (100 ± 0,1) g.

Exept as if the adhesive is dispensed from a dual cartridge a cup preferably disposable, with a flat bottom and of suitable size, made of a material that is not adversely affected by the adhesive to be tested, with a wall thickness of not more than 1 mm is required. Wax-coated disposable paper cups have depending on the exotherm of the adhesive and the softening point of the wax coating a potential influence on the test result.

For manual mixing a spatula made of a material which does not react with the adhesive under test having at least one square (not rounded) end. Although disposable wooden spatulas can be used, stainless steel spatulas are preferred, especially for highly viscous adhesives due to their greater mechanical stability and for polyurethane adhesives to prevent moisture from the wood reacting with the isocyanate component. Commonly available wooden spatulas have rounded ends. To avoid insufficient mixing in the corners between the bottom and the wall of the cup, the rounded end shall be cut-off before use.

A spatula is not required if mixing of the components is performed either using a dual asymmetric centrifuge (13.2.8) or if the adhesive is delivered in a dual cartridge and applied using a dispensing gun (13.2.9) via a static mixer (13.2.10).

As an alternative to manual mixing the use of a dual asymmetric centrifuge allowing rotation speeds of up to approx. 3 000 rpm^[8], together with a closable beaker suitable for the device (in accordance with the requirements provided in 13.2.6) with a volume adapted to the required amount of adhesive, provides typically excellent mixing results with short mixing times.

NOTE 1 The shear forces that occur during mixing cause the adhesive mixture to heat up, which affects the pot life value determined.

If the adhesive is delivered in a dual cartridge it can be directly dispensed by the use of a suitable dispensing gun together with a suitable static mixer tip (13.2.10) is required. Manual, compressed air and battery-operated guns are suitable..

If the adhesive is dispensed from a dual cartridge a static mixer tip specified and approved for the respective adhesive shall be used.

With an uncertainty of measurement < ±1 s.

Equipped with a load cell that the fracture of the specimen should occure at a force between 10 % and 80 % of the full load capacity. The response time of the machine shall be short enough that the force applied at the time of break can be measured accurately. The recorded force shall not deviate from the actual force applied by more than 1 %.

The machine shall be equipped with a suitable pair of grips allowing to compensate the misalignment caused by the overlap and the bondline between the two adherends of the specimen. The specimen grips and their mountings shall be designed so that the longitudinal axis of the specimen coincides with the direction of the applied force through the centre line of the specimen grips.

Grips that operate by bolting through the adherends should not be used since such grips can lead to undesirable stress peeks which further result in premature failure of the adherend.

The components of the adhesive are separately condition to an uniform agreed temperature using the temperature control device (13.2.2).

NOTE 1 (23 ± 2) °C is commonly used.

The time necessary for conditioning depends on the type and mass of adhesive concerned and shall be determined for each adhesive before starting the test.

The sample of mixed adhesive required for the measurement can be prepared from the conditioned individual components of the multi-component adhesive in different ways:

— If the adhesive is available in a dual cartridge, use a suitable dispensing gun (13.2.9) to apply the adhesive from the double cartridge onto the adherends (13.2.3) through the static mixer (13.2.10).

Before dispensing the adhesive the common steps of levelling the cartridge plungers before attaching the static mixer tip and discarding at least one mixer volume shall be performed.

Start the stopwatch (13.2.11) at the time when starting applying the adhesive to the adherends (13.2.3).

— In case the adhesive is not available in a dual cartridge use a suitable balance (13.2.5) to weigh the individual components into a cup (13.2.6) of appropriate size observing the mixing ratio specified by the manufacturer for the particular adhesive. The quantity of adhesive mixed shall be sufficient to prepare the required number of tensile shear test specimens. However, it shall be ensured that only as much adhesive is mixed per mixing process as can be applied to the adherends within half the expected pot life.

Start the stopwatch (13.2.11) and mix the adhesive with the square (not rounded) end of the spatula (13.2.7) for (60 ± 10) s. Take care that the areas in the angle between the side and bottom of the cup are well mixed and avoid mixing-in of air.

Instead of manual mixing using a spatula, a laboratory dual asymmetric centrifuge mixing system (13.2.8) can be used. Consider the material warming that occurs as a result of the mixing process.

Apply the mixed adhesive to one of the adherends (13.2.3) to prepare the tensile lap shear specimens in accordance to ISO 4587.

Place the spacers (13.2.4) to ensure the specified thickness of the adhesive joint.

In order to eliminate the use of spacers, it is also possible to use special joining devices that by design ensure the specified adhesive layer thickness.

The second adherend is joined after 50 - 60 % of the pot life of the adhesive used has elapsed.

In a first series of at least 3 test specimens, one adherend is displaced by 5 ± 1 mm in the direction of the test specimen width and then immediately returned to its original position. Care shall be taken to ensure that the displacement is parallel to the bond surface without changing the adhesive layer thickness, even temporarily.

For further series, again with at least 3 test specimens each, displacing and repositioning of the adherend is performed according to staggered time periods, whereby the time intervals between the series become shorter as the expected working life approaches. For the last series, this should take place well after the expected working life has expired.

The test specimens are cured according to the adhesive manufacturer’s recommendation or according to the cure conditions used for the specific bonding process.

Destructive testing of samples cured at room temperature (commonly at 23 °C ± 2 °C) is typically carried out after 7 days at the earliest.

Specimens cured at elevated temperature should be conditioned at room temperature (commonly 23 °C ± 2 °C) for at least 24 h before destructive testing.

The destructive test is carried out at a specified speed in accordance with ISO 4587 using the tensile testing machine (13.2.12). The highest force during rupture is recorded as the breaking force for each specimen.

For each test specimen, the highest force during fracture is recorded as the breaking force (together with the type of failure determined in accordance with ISO 10365.

The lap shear strength is calculated according to Formula (4)

(4)

where

is the lap shear strength in N/mm² or MPa;

is the strength at break, in N;

is the overlap length in mm;

is the width of the bonded area in mm;

A is the bond area in mm².

For each series of at least three to five specimens the lap shear strength is expressed as the median, for series with more than five specimens as the mean value including the standard deviation.

The working life is the maximum time between mixing the adhesive and the point at which moving the adherends relative to each other does not result in a significant reduction in lap shear strength or a significant increase in the proportion of adhesive failure.

The test report shall include the following information:

a) a reference to this document, i.e. ISO 10364, and the reference number of the method used;

b) the working life determined as the time elapsed between mixing the adhesive and joining the second adherend after which no significant reduction in the tensile tap shear strength or a significant increase in the proportion of adhesive failure is observed;

c) all details necessary for complete identification of the adhesive, including type, source, the manufacturer's code number, form and batch number and/or date of manufacture;

d) material of the lap shear test;

e) geometry of the dispensed bead (i.e. length, width and hight);

f) total amount of mixed adhesive;

g) specified mixing ratio;

h) actual mixing ratio;

i) mixing process used;

j) dimensions and material of the cup used for mixing;

k) if a dual asymmetric centrifuge mixing system was used, mixing time and speed in rpm;

l) if dispensed from a dual cartridge type and size as well as description of mixer tip used (type, diameter and number of mixing elements);

m) temperature at which the adhesive was conditioned for application;

n) ambient temperature during the test;

o) temperature at which the adhesive was conditioned for application;

p) ambient temperature during preparation of the lap shear test specimens;

q) material and surface preparation of the adherends;

r) a complete description of the specimens, including;

— dimensions of the adherends (length, width, thickness);

— overlap length;

— bondline thickness;

— type of spacers used;

— time of joining process as a percentage of pot life;

s) temperature during destructive the test;

t) the speed of destructive testing;

u) for each individual test specimen;

— the breaking force for each individual specimen;

— the lap shear strength for each individual specimen;

— the failure mode according to ISO 10365;

v) for each individual test series;

— the mean, respectively average breaking force;

— the mean, respectively average lap shear strength;

— the mean, respectively average failure mode according to ISO 10365;

w) any relevant observations, such as setting, discoloration, separation, caking or gelling, which might have influenced the usability of the adhesive;

x) any other factors which might have influenced the result;

z) date of the test.

Bibliography

[1] ISO 4587, Adhesives — Determination of tensile lap-shear strength of rigid-to-rigid bonded assemblies

[2] ISO 6237, Adhesives — Wood-to-wood adhesive bonds — Determination of shear strength by tensile loading

[3] ISO 8510‑2, Adhesives — Peel test for a flexible-bonded-to-rigid test specimen assembly — Part 2: 180° peel

[4] ISO 9653, Adhesives — Test method for shear impact strength of adhesive bonds

1. “Speedmixer^TM” from Hauschildt or “Thinky Mixer” from Thinky Corporation are examples of suitable products available commercially. This information is given for the convenience of users of this document and does not constitute an endorsement by ISO of these products. ↑

2. “Speedmixer^TM” from Hauschildt or “Thinky Mixer” from Thinky Corporation are examples of suitable products available commercially. This information is given for the convenience of users of this document and does not constitute an endorsement by ISO of these products. ↑

3. “Speedmixer^TM” from Hauschildt or “Thinky Mixer” from Thinky Corporation are examples of suitable products available commercially. This information is given for the convenience of users of this document and does not constitute an endorsement by ISO of these products. ↑

4. “Speedmixer^TM” from Hauschildt or “Thinky Mixer” from Thinky Corporation are examples of suitable products available commercially. This information is given for the convenience of users of this document and does not constitute an endorsement by ISO of these products. ↑

5. “Speedmixer^TM” from Hauschildt or “Thinky Mixer” from Thinky Corporation are examples of suitable products available commercially. This information is given for the convenience of users of this document and does not constitute an endorsement by ISO of these products. ↑

6. “Speedmixer^TM” from Hauschildt or “Thinky Mixer” from Thinky Corporation are examples of suitable products available commercially. This information is given for the convenience of users of this document and does not constitute an endorsement by ISO of these products. ↑

7. “Speedmixer^TM” from Hauschildt or “Thinky Mixer” from Thinky Corporation are examples of suitable products available commercially. This information is given for the convenience of users of this document and does not constitute an endorsement by ISO of these products. ↑

8. “Speedmixer^TM” from Hauschildt or “Thinky Corporation Mixer” from Thinky Corporation are examples of suitable products available commercially. This information is given for the convenience of users of this document and does not constitute an endorsement by ISO of these products. ↑