ISO INTERNATIONAL STANDARD 2270 Second edition 1989-08-15 Asl Interrat Doc Seo Non-ionic surface active agents Polyethoxylated derivatives - lodometric determination of oxyethylene groups Agents de surface non ioniques - Derives polyethoxyles - Dosage iodometrique desgroupesoxyethylene Referencenumber ISO 2270:1989 (E) e with ISO No reproduction or networking permited without license from IHS Not for Resale ISO 2270 : 1989 (E) 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 technicai 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, govern- mental 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. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the Iso Council. They are approved in accordance with ISO procedures requiring at least 75 % approval by the member bodies voting International Standard ISO 2270 was prepared by Technical Committee ISO/TC 91, Surface active agents. This second edition cancels and replaces the first edition (IS0 2270 : 1972), of which it constitutes a minor revision. ? ISO 1989 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. International Organization for Standardization Case postale 56. CH-1211 Geneve 20. Switzerland Printed in Switzerland Copyright Intemational Organization for Standardization Not for Resale ISO 2270 : 1989 (E) INTERNATIONAL STANDARD Non-ionic surface active agents - Polyethoxylated derivatives -- lodometric determination of oxyethylene groups Scope 3Principle 7 This Internationai Standard specifies a method for the iodometric determination of oxyethylene groups in poly- acid. ethoxylated non-ionic surface active agents. Liberation of the iodine and titration with a standard volumetric The method is applicable to the analysis of polyethoxylated sodium thiosulfate solution. derivatives of primary saturated fatty alcohols; 4 Reactions oleylalcohol The basic reaction is the conversion of each (CH2-CH2O) group saturated fatty acids; to ethylene di-iodide (ICH2-CH2l), in accordance with the equa- tion straight and branched chain alkyliphenols. RO-(CH2-CH2O), H + 2nHI→ nlCH2-CH2l + ROH + nH20 It is also applicable in the presence of unreacted alcohols, fatty acids or alkylphenols of the types mentioned above. The unstable ethylene di-iodide is then decomposed on heating: The method is not applicable in the presence of ICH2-CH2l -→ C2H4 + 12 compounds containing sulfur or nitrogen; NOTE - If R is an alkyl radical, ROH will be converted to RI. Some of compounds containing oxygen or halogen atoms on the ethylene groups (and all of any oleyl alcohol present) wil react with adjacent carbon atoms other than as oxyethylene groups, HI to form a stable iodide. for example compounds containing oxypropylene groups; aldehydes or acetals; 5. Reagents sterols and derivatives. During the analysis, use only reagents of recognized analytical grade and only distlled water or water of equivalent purity. 2 Normative references 5.1 Nitrogen or carbon dioxide. The following standards contain provisions which, through reference in this text, constitute provisions of this International 5.2 Potassium iodide, crystais, minimum purity 99,5 %. Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to