ISO INTERNATIONAL STANDARD 13773 First edition 1997-07-15 Rubber Polychloroprene latex Determination of alkalinity Caoutchouc - Latex de polychloroprene - Determination de I'alcalinité This material is reproduced from Iso documents under International Organization for Standardization (ISo) Copyright License number IHS/lcC/1996. Not for resale. No part of these Iso documents maybe reproduced in any form, electronic retrieval system or otherwise, except as aliowed inthe copyright law ofthe country of use, or withthepriorwritten consent of iso (Case postale 56, 1211 Geneva 20, Switzerland, Fax +41 22 7341079),IHsortheISOLicensor'smembers. ISO Reference number ISO 13773:1997(E) Copyright Intermational Organization for Standardization No reproduction or networking permitted without license from IHS Not for Resale ISO 13773:1997(E) Foreword ISO (the Intemational 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. International Standard ISO 13773 was prepared by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 3, Raw materials (including latex) for use in the rubber industry. Annexes Aand Bofthis International Standardareforinformationonly. C1SO1997 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic InternationalOrganizationforStandardization Case postale 56 : CH-1211 Geneve 20 . Switzeriand Intemet: [email protected] X.400: C=ch; a=400net; p=iso; o=isocs; S=central Printed in Switzerland n for Standardization S unde Not for Resale ISO 13773:1997(E) INTERNATIONAL STANDARD @ISO Rubber - Polychloroprene latex - Determination of alkalinity This standard does not purport to address all of the safety problems, if any, associated with its use. It is the with any national regulatory conditions. 1 Scope This International Standard specifies a method for the determination of the alkalinity of polychloroprene latex prepared by the polymerization of chloroprene in an alkaline emulsion. It is not suitable for polychloroprene latex prepared in a non-ionic emulsion, for natural rubber latex concentrate nor necessarily for synthetic rubber latices otherthan polychloroprene. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. All standards are subject to revision, and parties to agreements based on this International indicated below. Members of iEC and IsO maintain registers of currently valid International Standards. ISO 123:1985, Rubber latex Sampling. IsO 976:1996, Rubber and plastics --Polymer dispersions and rubber latices Determination of pH. IsO 3696:1987, Water foranalytical laboratory use -- Specification and test methods. 3 Principle A test portion of the latex is titrated electrometrically against hydrochloric acid to the second point of inflexion of the titration curve (pH in the range 4 to 5). The alkalinity is calculated from the amount of acid required. The alkalinity is commonly expressed as its two component parts in practice, i.e. the amount of acid required to the first point of inflexion (pH in the range 1o to 11) which measures the amount of free alkali (the alkaline reserve) and the amount of additional acid required to the second point of inflexion which is a measure of the amount of saponified anionic organic surfactants in the latex, usually refered to as