ISO INTERNATIONAL STANDARD 28641 Second edition 2018-06 Rubber compounding ingredients - Organic chemicals General test methods Ingrédients de melange du caoutchouc Produits chimiques organiques -Méthodes d'essai générales Reference number IS0 28641:2018(E) ISO @IS02018 IS0 28641:2018(E) COPYRIGHTPROTECTEDDOCUMENT @ IS0 2018 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. ISO copyright office CP 401 : Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +4122 749 0111 Fax: +41 22 749 09 47 Email: [email protected] Website: www.iso.org Published in Switzerland ii @ IS0 2018 - All rights reserved IS0 28641:2018(E) Contents Page Foreword ..V 1 Scope ..1 2 Normative references 3 Terms and definitions 4 Abbreviated terms ..2 5 General requirements. 5.1 Thermometer .2 5.2 Desiccator. .2 6 Sampling: .2 6.1 Apparatus .2 6.2 Sampling method. .2 7 Test methods. .2 7.1 Density and relative density .2 7.1.1 .2 General. 7.1.2 Hydrometer method. 3 7.1.3 Pyknometer method .3 7.1.4 Expression of results. 6 7.1.5 Test report. .6 7.2 Loss on heating .6 7.2.1 General .6 7.2.2 Method A. .6 7.2.3 Method B. .7 7.2.4 Calculation. ..8 7.2.5 Expression of results 9 7.2.6 Precision. .9 7.2.7 Test report. 9 7.3 Sieve residue ..9 7.3.1 General. .9 7.3.2 Principle .9 7.3.3 Reagents. .9 7.3.4 Apparatus .10 7.3.5 Procedure. .10 7.3.6 Calculation. .11 7.3.7 Expression of results ..11 7.3.8 Precision. .11 7.3.9 Test report. 11 7.4 pH of water extract .11 7.4.1 Principle. .11 7.4.2 Apparatus. .11 7.4.3 Procedure. .12 7.4.4 Test report. ..12 7.5 Melting point. 13 7.5.1 General. .13 7.5.2 Method A .13 7.5.3 Method B. ..13 7.5.4 Method C ..14 7.5.5 Expression of results .14 7.5.6 Precision. .15 7.5.7 Test report ..15 7.6 Temperature of solidification .15 7.6.1 Principle ..15 7.6.2 Apparatus. ..15 @ IS0 2018 - All rights reserved ii