ISO INTERNATIONAL STANDARD 11501 First edition 1995-09-15 Plastics -- Film and sheeting Determination of dimensional change on heating Plastiques -Film et feuille -Determination de la variation dimensionncllcapreschauffage ISO Rcfcrence number ISO 11501:1995(E) IS0 11501:1995(E) Foreword ISO (the International Organization for Standardization) is a worldwide 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 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 voting.Publication as an International a vote. International StandardIsO11501waspreparedbyTechnicalCommittee ISO/TC61,Plastics,SubcommitteeSC11,Products. Annex A of this International Standard is for information only ISO 1995 Al rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microtilm, without permission in writing from the publisher. International Organization for Standardization Case Postale 56· CH-1211 Geneve 20· Switzerland Printed in Switzerland ii INTERNATIONALSTANDARDISO ISO11501:1995(E) Plastics Film and sheeting - Determination of dimensional change on heating Scope 1 4 Apparatus This International Standard specifies a method of de- 4.1 Circulating-air oven, of such a size that the termining the dimensional change, in the longitudinal total volume of thetest assemblies (kaolinbeds plus and transverse directions, of plastic films and sheeting test specimens)does not exceed 10% of thefree on heating. This method may be applied to plastic space in the oven. Provision shall be made for placing sheets, whether qualified as thermoshrinking or not, the test assemblies on shelvces so that they are not upto1mmthick. less than 50mm from each other and from the sides of the oven. Provision shall be made for circulation of air through Normative reference the oven at a rate which gives a minimum of six air changes per hour. The temperature of the oven shall The following standard contains provisions which, be thermostatically controlled to maintain the tem- through reference in this text, constitute provisions perature of the test assemblies within ± 2 'C of the of this International Standard.At the time of publi- specified temperature (within ± 1 C if the specified cation, the edition indicated was valid.All standards temperature is less than 100 °C). are subject to revision, and parties to agreements based on this International Standard are encouraged 4.2 Metal container, containing a kaolin bed of to investigate the possibility of applying the most re- depth approximately 20 mm.Its other dimensions cent edition of the standard indicated below. Mem- bers of IEC and ISo maintain registers of currently shall be such that the specimens can be placed flat within it, without deformation, and such that it can be valid International Standards. placed in the oven. IsO291:1977.Plastics Standard atmospheres for conditioning and testing. 4.3 Temperature-measuring device, whose tip can be immersed in the kaolin bed. Principle 4.4 Graduated scale, capable of mcasuring to the 3 nearest 0,5 mm. The test consists of 4.5S Stopwatch. a) measuring the initial lengths of two gauge lengths marked on each specimen in the longitudinal and 5 Test specimens in the transverse direction; Samples of film or sheet shall be conditioned for a b) heating the specimens for a specified time at a minimum of 2 h in one of the standard atmospheres specified temperature on a kaolin bed in an oven; specified in isO 291 prior to cutting out and measur- ing test specimens