1、BSI Standards PublicationBS ISO 1658:2015Natural rubber (NR) Evaluation procedureBS ISO 1658:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 1658:2015. Itsupersedes BS ISO 1658:2009 which is withdrawn.The UK participation in its preparation was entrusted t
2、o TechnicalCommittee PRI/50, Rubber - Raw, natural and synthetic, includinglatex and carbon black.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are respons
3、ible for its correctapplication. The British Standards Institution 2015. Published by BSI StandardsLimited 2015ISBN 978 0 580 89100 7ICS 83.060Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Polic
4、y and Strategy Committee on 31 July 2015.Amendments issued since publicationDate Text affectedBS ISO 1658:2015 ISO 2015Natural rubber (NR) Evaluation procedureCaoutchouc naturel (NR) Mthode dvaluationINTERNATIONAL STANDARDISO1658Fourth edition2015-08-01Reference numberISO 1658:2015(E)BS ISO 1658:201
5、5ISO 1658:2015(E)ii ISO 2015 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2015, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photoco
6、pying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 0
7、1 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 1658:2015ISO 1658:2015(E)Foreword iv1 Scope . 12 Normative references 13 Sampling and further preparative procedures . 14 Physical and chemical tests on raw rubber 24.1 Mooney viscosity . 24.2 Volatile-matter content 24.3 Other specifications
8、 on requirements 25 Preparation of test mix 25.1 General . 25.2 Standard test formulae 25.3 Procedure 35.3.1 Equipment and procedure . 35.3.2 Mill mixing procedure for formulae 1 and 2 (gum compounds) 35.3.3 Mill mixing procedure for formulae 1 and 2 (gum compounds) using masterbatches . 45.3.4 Mixi
9、ng procedures for formula 3 (black-filled compound) 46 Evaluation of vulcanization characteristics by a curemeter test . 86.1 Using an oscillating-disc curemeter 86.2 Using a rotorless curemeter 87 Evaluation of tensile stress-strain properties of vulcanized test mixes . 98 Test report . 9Annex A (n
10、ormative) Procedure for preparing gum compounds through use of masterbatches .10Annex B (informative) Precision statement for both mill and internal mixer .12Bibliography .17 ISO 2015 All rights reserved iiiContents PageBS ISO 1658:2015ISO 1658:2015(E)ForewordISO (the International Organization for
11、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 r
12、ight 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.The procedur
13、es used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial r
14、ules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights iden
15、tified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation
16、on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary informationThe committee responsible for this document is
17、ISO/TC 45, Rubber and rubber products, Subcommittee SC 3, Raw materials (including latex) for use in the rubber industry.This fourth edition cancels and replaces the third edition (ISO 1658:2009), of which it constitutes a minor revision to update the normative references (in Clause 2 and throughout
18、 the text).iv ISO 2015 All rights reservedBS ISO 1658:2015INTERNATIONAL STANDARD ISO 1658:2015(E)Natural rubber (NR) Evaluation procedureWARNING Persons using this International Standard should be familiar with normal laboratory practice. This standard does not purport to address all of the safety p
19、roblems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions.1 ScopeThis International Standard specifies physical and chemical tests on raw natural rubbers; standa
20、rd materials, standard test formulae, equipment and processing methods for evaluating the vulcanization characteristics of natural rubber (NR).2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. Fo
21、r dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 37, Rubber, vulcanized or thermoplastic Determination of tensile stress-strain propertiesISO 248-1, Rubber, raw Determination of volatile-m
22、atter content Part 1: Hot-mill method and oven methodISO 289-1, Rubber, unvulcanised Determinations using a shearing-disc viscometer Part 1: Determination of Mooney viscosityISO 1795, Rubber, raw natural and raw synthetic Sampling and further preparative proceduresISO 2000:2014, Rubber, raw natural
23、Guidelines for the specification of technically specified rubber (TSR)ISO 2007, Rubber, unvulcanized Determination of plasticity Rapid-plastimeter methodISO 2393, Rubber test mixes Preparation, mixing and vulcanization Equipment and proceduresISO 3417, Rubber Measurement of vulcanization characteris
24、tics with the oscillating disc curemeterISO 6502, Rubber Guide to the use of curemetersISO 23529, Rubber General procedures for preparing and conditioning test pieces for physical test methods3 Sampling and further preparative procedures3.1 A laboratory sample of mass approximately 1,5 kg shall be p
25、repared by the method described in ISO 1795.3.2 The rubber shall be homogenized in accordance with ISO 1795.3.3 Preparation of the test samples shall be in accordance with ISO 1795. ISO 2015 All rights reserved 1BS ISO 1658:2015ISO 1658:2015(E)4 Physical and chemical tests on raw rubber4.1 Mooney vi
26、scosityDetermine the Mooney viscosity in accordance with ISO 289-1 on a test sample prepared as indicated in 3.3. Record the result as ML(1+4) at 100 C.4.2 Volatile-matter contentDetermine the volatile-matter content by the oven method specified in ISO 248-1 on a test sample prepared as indicated in
27、 3.3.4.3 Other specifications on requirementsAny specific values for physical and chemical properties other than the above (4.1 and 4.2) shall be based upon the grades given in Table 2 of ISO 2000:2014.5 Preparation of test mix5.1 GeneralThe following standard formulae and mixing procedures are reco
28、mmended:a) two gum-stock formulae for comparative testing of the vulcanization characteristics of natural rubber for use in non-black-filled compounds;b) a black-filled formula for comparative testing of natural rubber for use in black-filled compounds;c) a mill mixing procedure including masterbatc
29、hes for the two gum-stock formulae;d) a mill mixing procedure and a laboratory internal mixer (LIM) mixing procedure for the black-filled formula.NOTE The black-filled formula (formula 3 in Table 1) can also be used for comparative testing of isoprene rubbers (IRs).5.2 Standard test formulaeThe stan
30、dard test formulae are given in Table 1.The materials shall be national or international standard reference materials.2 ISO 2015 All rights reservedBS ISO 1658:2015ISO 1658:2015(E)Table 1 Standard test formulaeMaterialNumber of parts by massFormula (1) ACS 1Formula (2) TBBS 1Formula (3) Black-filled
31、Natural rubber 100,00 100,00 100,00Zinc oxide 6,00 6,00 5,00Sulfur 3,50 3,50 2,25Stearic acid 0,50 0,50 2,00Industry reference black a 35,00MBT b0,50 TBBS c 0,70 0,70Tot al 110,50 110,70 144,95aThe current IRB shall be used.b2-Mercaptobenzothiazole.cN-tert-butyl-2-benzothiazole-sulfenamide. This sha
32、ll be in powder form having an initial ether-insoluble or ethanol-insoluble matter content of less than 0,3 % (by mass). The material shall be stored at room temperature in a closed container and the ether-insoluble or ethanol-insoluble matter shall be checked every 6 months. If this is found to exc
33、eed 0,75 % (by mass), the material shall be discarded or recrystallized.5.3 Procedure5.3.1 Equipment and procedureEquipment and procedure for the preparation, mixing and vulcanizing shall be in accordance with ISO 2393.5.3.2 Mill mixing procedure for formulae 1 and 2 (gum compounds)The standard labo
34、ratory mill batch mass, in grams, shall be four times the formulation batch mass (i.e. 110,5 g 4, = 442 g, for formula 1). Maintain the surface temperature of the rolls at 70 C 5 C and a good rolling bank at the nip of the rolls during mixing. If this is not obtained with the nip settings specified
35、hereunder, small adjustments to the mill openings might be necessary.Duration (min)a) Pass the rubber twice between the rolls without banding, with the mill opening set at 0,2 mm.b) Band the rubber with the mill opening set at 1,4 mm. When a smooth band has been obtained, adjust the mill opening to
36、1,8 mm.4c) Add the zinc oxide, the stearic acid, the sulfur and the MBT or TBBS. 4d) Make three 3/4 cuts from each side. 3e) Cut the batch from the mill. Set the mill opening to 0,8 mm and pass the rolled batch endwise through the rolls six times.2_Total time 13f) Check the mass of the batch (see IS
37、O 2393). If the mass of the batch differs from the theoretical value by more than + 0,5 % or 1,5 %, discard the batch and remix. ISO 2015 All rights reserved 3BS ISO 1658:2015ISO 1658:2015(E)g) Cut sufficient material from the batch for curemeter testing and, if required, for determination of the Mo
38、oney viscosity of the unvulcanized batch in accordance with ISO 289-1. Sheet the batch to approximately 2,2 mm for preparing test slabs or to the appropriate thickness for preparing ISO ring test pieces.h) Condition the batch for 2 h to 24 h after mixing and prior to vulcanizing, if possible at stan
39、dard temperature and humidity as defined in ISO 23529.5.3.3 Mill mixing procedure for formulae 1 and 2 (gum compounds) using masterbatchesCompounding materials such as accelerators, sulfur or fillers can be incorporated into the rubber as masterbatches. This technique improves the accuracy of compou
40、nding-material incorporation and is also more convenient.The procedure for preparing masterbatches and test mixes for the gum compounds is given in Annex A.5.3.4 Mixing procedures for formula 3 (black-filled compound)5.3.4.1 Mill mixing5.3.4.1.1 Measurement of rapid plasticity numberLoad the rubber
41、on to the mill with the mill opening set at 0,5 mm. Masticate until a smooth band and rolling bank are obtained.After mastication, determine the rapid plasticity number in accordance with ISO 2007. The rapid plasticity number shall not exceed 45, which is approximately equivalent to a viscosity of 7
42、0 Mooney units determined in accordance with ISO 289-1.5.3.4.1.2 MixingThe standard laboratory mill batch mass, in grams, shall be four times the formulation batch mass (i.e. 144,95 g 4, = 579,8 g, for formula 3). Maintain the surface temperature of the rolls at 70 C 5 C and a good rolling bank at t
43、he nip of the rolls during mixing. If this is not obtained with the nip settings specified hereunder, small adjustments to the mill openings may be necessary.Duration (min)a) Band the rubber with the mill opening set at 1,4 mm. 1b) Add the stearic acid. Make one 3/4 cut from each side. 1c) Add the z
44、inc oxide and the sulfur. Make one 3/4 cut from each side. 2d) Add the carbon black evenly across the mill at a uniform rate. When about half the black has been incorporated, open the mill to 1,9 mm and make one 3/4 cut from each side. Then add the remainder of the carbon black. When all the black h
45、as been incorporated, make one 3/4 cut from each side. Be certain to add the black that has dropped into the mill pan.10e) Add the TBBS. Make three 3/4 cuts from each side. 3f) Cut the batch from the mill. Set the mill opening to 0,8 mm and pass the rolled batch lengthways through the mill six times
46、.3_Total time 204 ISO 2015 All rights reservedBS ISO 1658:2015ISO 1658:2015(E)g) Check the mass of the batch. If the mass of the batch differs from the theoretical value by more than + 0,5 % or 1,5 %, discard the batch and remix.h) Cut sufficient material from the batch for curemeter testing and, if
47、 required, for determination of the Mooney viscosity of the unvulcanized batch in accordance with ISO 289-1. Sheet the batch to approximately 2,2 mm for preparing test slabs or to the appropriate thickness for preparing ISO ring test pieces.i) Condition the batch for 2 h to 24 h after mixing and pri
48、or to vulcanizing, if possible at standard temperature and humidity as defined in ISO 23529.5.3.4.2 Mixing using a laboratory internal mixer (LIM)5.3.4.2.1 GeneralFor laboratory internal mixers having nominal capacities of 65 cm3to about 2 000 cm3, the batch mass shall be equal to the nominal mixer
49、capacity, in cubic centimetres, multiplied by the density of the compound, in grams per cubic centimetre. This means that, if the laboratory internal mixer has a nominal capacity of 750 cm3, the batch mass for formula 3 is 750 1,103 g (= 827,25 g).For each batch mixed during the preparation of a series of identical mixes, the laboratory internal mixer conditions shall be the same. At the beginning of each series of test mixes, a machine-conditioning batch sh
