ISO INTERNATIONAL STANDARD 305 Third edition 2019-05 Plastics Determination of thermal stability of poly(vinyl chloride), related chlorine-containing homopolymers and copolymers and their compounds Discoloration method Plastiques - Détermination de la stabilité thermique du poly(chlorure de vinyle), des homopolymeres et copolymeres chlorés apparentes et de leurs compositions - Methode du changement de couleur Reference number IS0 305:2019(E) @ IS0 2019 IS0 305:2019(E) COPYRIGHTPROTECTEDDOCUMENT @ IS0 2019 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: +41 22 749 01 11 Fax: +41 22 749 09 47 Email: [email protected] Website: www.iso.org Published in Switzerland i @ IS0 2019 - All rights reserved IS0 305:2019(E) Contents Page Foreword .iv 1 Scope. 1 2 Normative references 1 3 Terms and definitions 4 Principle 1 4.1 Method A: Oil-bath method 1 4.2 Method B: Oven method 2 5 Preparation and number of test specimens 2 6 Test temperature. .2 7 Method A: Oil-bath method .2 7.1 Apparatus. 2 7.2 Procedure 3 8 Method B: Oven method .3 8.1 Apparatus. 3 8.2 Procedure 4 9 Expression of results .4 10 Precision. .5 11 Test report. .5 Bibliography 6 @ IS0 2019 - All rights reserved iii