SANS 3387-2003 Rubber - Determination of crystallization effects by hardness measurements《橡胶 硬度测量法测定结晶效应》.pdf

1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA

2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any

3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ICS 83.060 ISBN 0-626-14754-9 SANS 3387:2003 Edition 1 and ISO tech. corr. 1 ISO 3387:1994 Edition 2 and tech. corr. 1 SOUTH AFRICAN NATIONAL STANDARD Ru

4、bber Determination of crystallization effects by hardness measurements This national standard is the identical implementation of ISO 3387:1994 and technical corrigendum No. 1 is adopted with the permission of the International Organization for Standardisation. Published by Standards South Africa 1 d

5、r lategan road groenkloof private bag x191 pretoria 0001 tel: 012 428 7911 fax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa 2003 SANS 3387:2003 Edition 1 and ISO tech. corr. 1 ISO 3387:1994 Edition 2 and tech. corr. 1 Table of changes Change No. Date Scope ISO tec

6、h. corr. 1 2000-04-15 Amended to add the following normative reference in Clause 2: ISO 7619:1997, Rubber Determination of indentation hard-ness by means of pocket hardness meters, and to a reference to ISO 7619 in subclause 4.2. National Foreword This South African standard was approved by National

7、 Committee STANSA TC 5140.17, Rubber and rubber products, in accordance with procedures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement. ICS 83.060.00 Ref. No. ISO 3387:1994/Cor.1:2000(E) ISO 2000 All rights reservedPrinted in SwitzerlandINTERNATIONAL STANDARD ISO 3387

8、:1994TECHNICAL CORRIGENDUM 1Published 2000-04-15INTERNATIONAL ORGANIZATION FOR STANDARDIZATION Gb7 Gb7 ORGANISATION INTERNATIONALE DE NORMALISATIONRubber Determination of crystallization effects by hardnessmeasurementsTECHNICAL CORRIGENDUM 1Caoutchouc Dtermination des effets de la cristallisation au

9、 moyen de mesurages de duretRECTIFICATIF TECHNIQUE 1Technical Corrigendum 1 to ISO 3387:1994 was prepared by Technical Committee ISO/TC 45, Rubber and rubberproducts, Subcommittee SC 2, Testing and analyses.Page 1Clause 2Add the following normative reference:ISO 7619:1997, Rubber Determination of in

10、dentation hardness by means of pocket hardness meters.Page 2Subclause 4.2Add a reference to ISO 7619 by replacing the first sentence as follows:“Hardness gauges, in accordance with ISO 48 or ISO 7619.”ISO 3387:1994/Cor.1:2000(E)2 ISO 2000 All rights reservedPage 3Subclause 6.1Replace the first sente

11、nce, “Carry out hardness measurement in accordance with ISO 48.”with the following text:“Carry out the hardness measurement in accordance with ISO 48 or ISO 7619. The method selected shall be usedfor the entire test.”INTERNATIONAL STANDARD ISO 3387 Second edition 1994-06-0 1 Rubber - Determination o

12、f crystallization effects by hardness measurements Caoutchouc - Determination des effets de Ia cristallisation au moyen de mesurages de duret6 Reference number ISO 3387:1994(E) ISO 3387:1994(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national St

13、andards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Esch member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International o

14、rganizations, 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. Draft International Standards adopted by the technical committees ar

15、e circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard ISO 3387 was prepared by Technical Committee ISO/TC 45 Rubber and rubber products, Subcommittee SC 2, Physical and deg

16、raia tion tests. This second edition cancels and replaces the first edition (ISO 3387:1978), of which it constitutes a minor revision. 0 ISO 1994 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronie or mech

17、anical, including photocopying and microfilm, without Permission in writing from the publisher. International Organization for Standardization Case Postale 56 l CH-l 211 Geneve 20 l Switzerland Printed in Switzerland ii INTERNATIONAL STANDARD 0 ISO ISO 3387: 1994(E) Rubber - Determination of crystal

18、lization effects by hardness measurements 1 Scope This International Standard specifies a test based on hardness measurements for determining the pro- gressive stiffening of rubber with time, caused by ctystallization. It is limited to materials having an initial hardness at test temperature of 10 I

19、RHD to 85 IRHD. The method is applicable to raw, unvulcanized (com- pounded), and vulcanized rubber. lt is mainly of inter- est for rubber with a marked crystallization tendency at temperatures experienced in cold climates, such as, for instance, chloroprene and natura1 rubber. The method is not app

20、licable to fast-crystallizing ma- terials which crystallize to a considerable degree within the time-span of 15 min used for conditioning at test temperature. 2 Normative references The following Standards contain provisions which, through reference in this text, constitute provisions of this Intern

21、ational Standard. At the time of publica- tion, the editions indicated were valid. All Standards are subject to revision, and Parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most re- cent editions of the Standards indicated bel

22、ow. Members of IEC and ISO maintain registers of cur- rently valid International Standards. ISO 4811994, Rubber, vulcanized or thermoplastic - Determination of hardness (hardness between 10 IRHD and 100 IRHD). ISO 47 1 :-1, Rubber - Times, temperatures and hu- midities for conditioning and testing.

23、ISO 1826: 1981, Rubber, vulcanized - Time-in terval between vulcanization and tes ting - Specifica tion. ISO 3383:1985, Rubber - General directions for achieving elevated or subnormal temperatures for test purposes. ISO 4661-1: 1993, Rubber, vulcanized or thermoplastic - Preparation of samples and t

24、est pieces - Part 1: Ph ysical tes ts. 3 Principle One of the following measurements is made on a test piece stored at the desired temperature: a) the increase in hardness after a specified storage time; b) the time required for a specified increase in hard- ness to occur. Tests may be carried out o

25、n test pieces of different thicknesses. These do not necessarily give the same values of hardness readings. Tests intended to be comparable shall be made on test pieces of the same thickness. The different methods of calculating data to be re- ported may give somewhat different values. Com- parisons

26、 of values obtained with different methods shall be avoided. 1) To be published. (Revision of ISO 471:1983) ISO 3387:1994(E) 4 Apparatus 0 ISO Table 1 Dimensions in millimetres 4.1 Cold chamber, in accordance with ISO 3383, capable of being maintained within + 1 “C of the - specified temperature and

27、 using a gaseous heat- transfer medium. As all final handling and measurements are to be made within the cold chamber, it shall be possible to perform these operations while the test piece tem- perature remains within the permissible variations. This may be done by providing suitable equipment which

28、 permits manipulation of materials within the chamber from the outside (for example by means of handholes and gloves through the door or wall of the cabinet). 4.2 Hardness gauges, in accordance with ISO 48. Lubricants, if used, shall be of a type not causing friction in the instrument at test temper

29、ature. 4.3 Tweezers or tongs, for handling of the test pteces. 4.4 Gloves, for handling of the test equipment. 4.5 Heated press, for the preparation of raw and unvulcanized (compounded) test pieces. 5 Test pieces 5.1 Dimensions The test piece shall have its upper and lower surfaces flat, smooth and

30、parallel to one another. The Standard test piece shall be 8 mm to 10 mm thick. Non- Standard test pieces may be either thicker or thinner, but in no case shall the test piece be thinner than 4 mm for hardnesses between 35 IRHD and 100 IRHD, or thinner than 6 mm for hardnesses be- tween 10 IRHD and 3

31、5 IRHD. The lateral dimensions of both Standard and non-Standard test pieces shall be such that no test is made at a distance from the edge of the test piece less than the appropriate dis- tance shown in table 1. 5.2 Preparation - Vulcanized rubber Test pieces of vulcanized rubber shall be prepared

32、in accordance with ISO 4661-1. To obtain the necessary thickness, it is permissible to superimpose two pieces of rubber (but no more than two) provided that these have flat, parallel surfaces. 5.3 Preparation - Raw and unvulcanized rubber Test pieces of raw and of unvulcanized (compounded) rubber sh

33、all be prepared by placing a suitable quantity in a preheated mould and then applying heat and pressure for a suitable time (see 4.5). The mould, still under pressure, shall be cooled to Standard temperature (see ISO 471). After 15 min, the pressure shall be released and the test piece re- moved. lt

34、 shall be free from blisters and porosity. Values of mould temperature and time of application of pressure required to produce a suitable test piece depend upon the type of rubber. A temperature of 150 “C applied for IO min has been found suitable for many raw rubbers, whilst a temperature of 120 “C

35、 applied for 3 min has been found satisfactory for many compounded rubbers. However, for some ma- terials, longer times or higher mould temperatures may be found necessary to ensure a smooth and flat test piece surface. Under no circumstances shall conditions be used that Cause incipient eure or de-

36、 gradation. 5.4 Conditioning 5.4.1 Time-interval between vulcanization and testing When appropriate, the time-interval between 0 ISO ISO 3387: 1994(E) vulcanization and testing shall be in accordance with ISO 1826. 5.4.2 Decrystallization and conditioning Test pieces of vulcanized rubber or test pie

37、ces moulded from raw or unvulcanized (compounded) rubber kept for more than 8 h after moulding before testing shall be decrystallized immediately before testing by heating them in an oven at 70 “C for 45 min. They shall then be conditioned at Standard temperature (see ISO 471) for at least 30 min an

38、d no more than 60 min before testing. 6 Procedure 6.1 Hardness measurement Carry out hardness measurement in accordance with ISO 48. Make one measurement at either three or five different Points distributed over the test piece and take the median of the results. Make each reading at a Point at least

39、 4 mm away from Points where any previous readings have been made. The Same hardness gauge shall be used throughout any one test, the appropriate gauge being determined from the initial hardness at test temperature. For initial hardnesses between IO IRHD and 30 IRHD, the in- strument specified for m

40、ethod L of ISO 48:1994 shall be used, for initial hardnesses between 30 IRHD and 80 IRHD the instrument specified for method N of ISO 48:1994 shall be used and for hardnesses over 80 IRHD, the instrument specified for method H of ISO 48:1994 shall be used. If the hardness increase gives values above

41、 35 IRHD for method L, the hard- ness readings shall be determined from an extension to table 5 of ISO 48:1994, calculated using the equation given in annex A of that Standard. 6.2 Original hardness First measure the hardness with the test piece and test equipment conditioned at the Standard tempera

42、- ture (see ISO 471). This measurement gives ad- ditional information but is not used in the calculation of crystallization effects and may be omitted for highly plastic samples of unvulcanized rubber. 6.3 Initial hardness at test temperature Condition the hardness gauge (4.2) and the tweezers or to

43、ngs (4.3) in the cold chamber (4.1) at the desired test temperature for at least 60 min. Place the test piece in the cold chamber at the de- sired test temperature. After 15 min + 1 min, take the first hardness reading, using the tweezers or tongs for handling the test piece and the gloves (4.4) for

44、 handling the test equipment. If the initial hardness reading is above 85 IRHD, the method is not applica- ble . NOTE 1 The hardness gauge used in this test procedure is normally conditioned and operated inside the cold cham- ber. Alternatively, a special device may be used where the body of the har

45、dness gauge is placed outside the cold chamber and connected with the indentor in the cold chamber by means of a rod with low heat-conductive ca- pacity, and constructed to avoid the introduction of ad- ditional f riction. 6.4 Hardness increase due to crystallization Repeat the hardness measurements

46、, as specified in 6.1, after the specified times of storage at test tem- perature. NOTE 2 After all measurements have been completed, it is advisable to dry all apparatus by warming it with circu- lating air to approximately 40 “C. 7 Temperature and duration of test 7.1 Temperature The test shall be

47、 carried out at one of the following temperatures (see ISO 471): + 23 “C + 2 “C (Standard temperature) + 27 “C AI 2 “C (Standard temperature) +10”c1 “C 0 “C + 1 “C - 10 “C + 1 “C - 25 “C + 1 “C - 40 “C I!I 1 “C - 55 “C + 1 “C - 70 “C + 1 “C If not specified for special reasons, the test shal carried

48、 out at the temperature which is closest to one where the crystallization rate is at its maxim whenever this is known. be the Jn 3 ISO 3387: 1994(E) 0 ISO NOTE 3 Generally crystallization rates are known to have their maxima at the following approxima te temperatures: Rubber polymer Chloroprene rubb

49、er Polyurethane rubber Natura1 rubber (1,4-cis-polyisoprene) Dimethyl Silicone rubber 1,4-cis-polybutadiene 7.2 Duration Temperature of maximum crystallization rate “C - IO - 10 - 25 - 55 - 55 Hardness measurements are generall (24 2) compound preparation details, and eure time and temperature, where appropriate; 3) method of preparation of test pieces from Sample; 4) thickness of test piece and whether made up of one or two pieces. b) Test method and test details: 1) number of this International Standard; 2) method by which the