1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS ISO 2303:2011Isoprene rubber (IR) Non-oil-extended, solution-polymerized types Evaluation proceduresBS ISO 2303:2011 BRITISH STANDARDNational forewordThis British Standard is
2、the UK implementation of ISO 2303:2011. Itsupersedes BS ISO 2303:2003 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee PRI/50, Rubber - Raw, natural and synthetic, includinglatex and carbon black.A list of organizations represented on this committee can
3、beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011ISBN 978 0 580 66330 7ICS 83.060Compliance with a British Standard cannot confer immunity fromlegal obligations.Thi
4、s British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 August 2011.Amendments issued since publicationDate Text affectedBS ISO 2303:2011Reference numberISO 2303:2011(E)ISO 2011INTERNATIONAL STANDARD ISO2303Fifth edition2011-08-15Isoprene rubber (IR)
5、Non-oil-extended, solution-polymerized types Evaluation procedures Caoutchouc isoprne (IR) Types polymriss en solution et non tendus lhuile Mthode dvaluation BS ISO 2303:2011ISO 2303:2011(E) COPYRIGHT PROTECTED DOCUMENT ISO 2011 All rights reserved. Unless otherwise specified, no part of this public
6、ation may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva
7、 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO 2011 All rights reservedBS ISO 2303:2011ISO 2303:2011(E) ISO 2011 All rights reserved iiiContents Page Foreword iv 1 Scope 1 2 Normative references 1 3 Sampling and sample prepara
8、tion . 2 4 Physical and chemical tests on raw rubber 2 4.1 Mooney viscosity . 2 4.2 Volatile matter 2 4.3 Ash 2 5 Preparation of the test mixes for evaluation of isoprene rubbers . 2 5.1 Standard test formulation . 2 5.2 Procedure . 3 5.2.1 Equipment and procedure 3 5.2.2 Mill mixing procedures . 3
9、5.2.3 Laboratory internal mixer (LIM) mixing procedure 4 6 Evaluation of vulcanization characteristics by a curemeter test . 8 6.1 Using an oscillating-disc curemeter 8 6.2 Using a rotorless curemeter . 8 7 Evaluation of tensile stress-strain properties of vulcanized test mixes . 8 8 Precision 9 9 T
10、est report 9 Annex A (informative) Precision data for both mill mixer and laboratory internal mixer 10 Annex B (informative) Additional precision data for natural rubber . 12 Bibliography 14 BS ISO 2303:2011ISO 2303:2011(E) iv ISO 2011 All rights reservedForeword ISO (the International Organization
11、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 t
12、he 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. Interna
13、tional Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publicatio
14、n as an International Standard requires approval by at least 75 % of the member bodies casting a vote. 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
15、. ISO 2303 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. This fifth edition cancels and replaces the fourth edition (ISO 2303:2003), in which the following technical changes have been made
16、: a laboratory internal mixer (LIM) mixing procedure has been added as Subclause 5.2.3; old Annex A, which gave an alternative mixing method using an internal mixer-mill mixing procedure, has been deleted; the existing precision data have been moved from Clause 8 to a new Annex A; precision data for
17、 the LIM mixing procedure have been added as Table A.2; precision data for natural rubber, obtained using mill mixing and LIM mixing, have been taken from ISO 1658:2009 and added as Annex B. BS ISO 2303:2011INTERNATIONAL STANDARD ISO 2303:2011(E) ISO 2011 All rights reserved 1Isoprene rubber (IR) No
18、n-oil-extended, solution-polymerized types Evaluation procedures WARNING Persons using this International Standard should be familiar with normal laboratory practices. This International Standard does not purport to address all of the safety problems, if any, associated with its use. It is the respo
19、nsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions. 1 Scope This International Standard specifies, for general-purpose non-oil-extended, solution-polymerized polyisoprene rubbers (IR): physical and chemical test
20、s on raw rubbers; standard materials, a standard test formulation, equipment and processing methods for evaluating the vulcanization characteristics. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the editi
21、on 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 properties ISO 247:2006, Rubber Determination of ash ISO 248-1, Rubber, raw Determination of
22、volatile-matter content Part 1: Hot-mill method and oven method ISO 289-1, Rubber, unvulcanized Determinations using a shearing-disc viscometer Part 1: Determination of Mooney viscosity ISO 1795, Rubber, raw natural and raw synthetic Sampling and further preparative procedures ISO 2393, Rubber test
23、mixes Preparation, mixing and vulcanization Equipment and procedures ISO 3417, Rubber Measurement of vulcanization characteristics with the oscillating disc curemeter ISO 6502, Rubber Guide to the use of curemeters ISO 23529, Rubber General procedures for preparing and conditioning test pieces for p
24、hysical test methods BS ISO 2303:2011ISO 2303:2011(E) 2 ISO 2011 All rights reserved3 Sampling and sample preparation 3.1 A laboratory sample of approximately 1,5 kg shall be taken by the method described in ISO 1795. 3.2 Preparation of the test portion shall be in accordance with ISO 1795. 4 Physic
25、al and chemical tests on raw rubber 4.1 Mooney viscosity The Mooney viscosity shall be determined in accordance with ISO 289-1 on a test portion prepared as described in ISO 1795 (without massing). The result shall be recorded as ML(1 4) at 100 C. 4.2 Volatile matter The volatile-matter content shal
26、l be determined in accordance with ISO 248-1. 4.3 Ash The ash content shall be determined in accordance with ISO 247. 5 Preparation of the test mixes for evaluation of isoprene rubbers 5.1 Standard test formulation The standard test formulation is given in Table 1. The materials shall be national or
27、 international standard reference materials. If no standard reference material is available, the materials to be used shall be agreed by the interested parties. Table 1 Standard test formulation for evaluation of IR rubbers Material Parts by mass Isoprene rubber (IR) 100,00 Stearic acid 2,00 Zinc ox
28、ide 5,00 Sulfur 2,25Industry reference black (N330) 35,00 TBBSa0,70Total 144,95aTBBS or N-tert-butylbenzothiazole-2-sulfenamide in accordance with ISO 6472. This shall be supplied in powder form having an initial insoluble-matter content, in accordance with ISO 11235, of less than 0,3 %. The materia
29、l shall be stored at room temperature in a closed container and insoluble matter shall be checked every 6 months. If this is found to exceed 0,75 %, the material shall be discarded. TBBS may be purified by reprocessing, e.g. by recrystallization; the procedure for this is beyond the scope of this In
30、ternational Standard. BS ISO 2303:2011ISO 2303:2011(E) ISO 2011 All rights reserved 35.2 Procedure 5.2.1 Equipment and procedure Equipment and procedure for the preparation, mixing and vulcanization shall be in accordance with ISO 2393. 5.2.2 Mill mixing procedures 5.2.2.1 General Two mill mixing pr
31、ocedures are specified: methods A and B. The mixing time is shorter in method B than in method A. The two methods do not necessarily give identical results. In laboratory cross-checks or in a series of evaluations, the same procedure shall be used in all cases. In both methods, the standard laborato
32、ry mill batch mass, in grams, shall be based on four times the formula mass. The surface temperature of the rolls shall be maintained at 70 C 5 C throughout the mixing. A good rolling bank at the nip of the rolls shall be maintained during mixing. If this is not obtained with the nip settings specif
33、ied in 5.2.2.2 and 5.2.2.3, small adjustments to the mill openings might be necessary. 5.2.2.2 Method A Duration Cumulative time(min) (min) a) Pass the rubber between the mill-rolls twice without banding, with the mill opening set at 0,5 mm, for approximately 2 min and weigh the rubber. 2,0 2,0 b) B
34、and the rubber with the mill opening set at 1,4 mm and make two 3/4 cuts from each side. 2,0 4,0 NOTE Some types of isoprene rubber go to the back roll, in which case the stearic acid should be added and, after its incorporation, the rubber can usually be transferred to the front roll. In addition,
35、certain tougher types of isoprene rubber might require slightly longer breakdown before the addition of other materials in order to obtain a good rolling bank.c) Set the mill opening to 1,7 mm and add the stearic acid. Make one 3/4 cut from each side. 2,0 6,0 d) Add the zinc oxide and the sulfur. Ma
36、ke two 3/4 cuts from each side. 3,0 9,0 e) Add the carbon black evenly across the mill at a uniform rate. When approximately 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. Be certain to add any black that
37、 has dropped into the mill pan. When all the black has been incorporated, make one 3/4 cut from each side. 13,0 22,0 f) Add the TBBS with the mill opening still at 1,9 mm. Make three 3/4 cuts from each side. 3,0 25,0 g) Cut the batch from the mill. Set the mill opening to 0,8 mm and pass the rolled
38、batch endwise through the rolls six times. 3,0 28,0 h) Sheet the batch to an approximate thickness of 6 mm and check-weigh the batch (see ISO 2393). If the mass of the batch differs from the theoretical value by more than 0,51, 5%, discard the batch and re-mix. BS ISO 2303:2011ISO 2303:2011(E) 4 ISO
39、 2011 All rights reservedi) Remove sufficient material from the batch for evaluating the vulcanization characteristics in accordance with ISO 3417 or ISO 6502. Condition this material for 2 h to 24 h, if possible at a standard temperature and humidity as defined in ISO 23529, before testing. j) Shee
40、t the batch to approximately 2,2 mm for preparing test slabs or to the appropriate thickness for preparing ISO ring test pieces in accordance with ISO 37. k) Condition the batch for 2 h to 24 h prior to vulcanizing, if possible at a standard temperature and humidity as defined in ISO 23529. 5.2.2.3
41、Method B Duration Cumulative time(min) (min) a) Pass the rubber between the rolls twice without banding, with the mill opening set at 0,5 mm 0,1 mm, then band the rubber between the rolls with the mill opening gradually increased to 1,4 mm. 2,0 2,0 b) Add the stearic acid. Make one 3/4 cut from each
42、 side. 2,0 4,0 c) Add the sulfur and the zinc oxide. Make two 3/4 cuts from each side. 3,0 7,0 d) Add half of the carbon black. Make two 3/4 cuts from each side. 3,0 10,0 e) Add the remaining half of the carbon black and any black that has dropped into the mill pan. Make three 3/4 cuts from each sid
43、e. 5,0 15,0 f) Add the TBBS. Make three 3/4 cuts from each side. 3,0 18,0 g) Cut the batch from the mill. Set the mill opening to 0,5 mm 0,1 mm and pass the rolled batch endwise through the rolls six times. 2,0 20,0 h) Sheet the batch to an approximate thickness of 6 mm and check-weigh the batch (se
44、e ISO 2393). If the mass of the batch differs from the theoretical value by more than 0,51, 5%, discard the batch and re-mix. i) Remove sufficient material from the batch for evaluating the vulcanization characteristics in accordance with ISO 3417 or ISO 6502. Condition this material for 2 h to 24 h
45、, if possible at a standard temperature and humidity as defined in ISO 23529, before testing. j) Sheet the batch to approximately 2,2 mm for preparing test slabs or to the appropriate thickness for preparing ISO ring test pieces in accordance with ISO 37. k) Condition the batch for 2 h to 24 h prior
46、 to vulcanizing, if possible at a standard temperature and humidity as defined in ISO 23529. 5.2.3 Laboratory internal mixer (LIM) mixing procedure 5.2.3.1 General For a LIM having a nominal mixing capacity of 65 cm3to about 2 000 cm3, the batch mass shall be equal to the nominal mixer capacity, in
47、cubic centimetres, multiplied by the compound density. The LIM conditions shall be the same for each batch mixed during the preparation of a series of identical mixes. At the beginning of each series of test mixes, a machine-conditioning batch shall be mixed using the same formulation as the mixes u
48、nder test. The LIM shall be allowed to cool down to 60 C between the end of one test batch and the start of the next. Temperature control settings shall not be altered during the mixing of a series of test batches. BS ISO 2303:2011ISO 2303:2011(E) ISO 2011 All rights reserved 55.2.3.2 Single-stage m
49、ixing procedure The mixing technique shall be such as to obtain a good dispersion of all the ingredients. The final temperature of the batch discharged after mixing shall not exceed 120 C. If necessary, adjust the batch mass, head temperature and/or rotor speed so that this condition is met. NOTE 1 Compounding materials other than rubber, carbon black and oil can be added to LIM batches more precisely and with greater ease if they are previously blended together in the p