1、BRITISH STANDARD BS ISO 706:2004 Rubber latex Determination of coagulum content (sieve residue) ICS 83.040.10 BS ISO 706:2004 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 3 November 2004 BSI 3 November 2004 ISBN 0 580 44691 3 National fore
2、word This British Standard reproduces verbatim ISO 706:2004 and implements it as the UK national standard. It supersedes BS 6057-3.8:1987 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee PRI/50, Rubber-raw, natural and synthetic, including latex and ca
3、rbon black, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international publications referred to in this document may be found in the BSI Catalogue under the s
4、ection entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application
5、. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor
6、related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the ISO title page, pages ii and iii, a blank page, pages 1 to 7 and a back cover. The BSI copyright notice displayed in this document indicat
7、es when the document was last issued. Amendments issued since publication Amd. No. Date CommentsINTERNATIONAL STANDARD ISO 706 Fourth edition 2004-10-15 Reference number ISO 706:2004(E) Rubber latex Determination of coagulum content (sieve residue) Latex de caoutchouc Dtermination de la teneur en co
8、agulum (refus sur tamis)BSISO706:2004ii BSISO706:2004OSI 7064002:)E(iii 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 tech
9、nical 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, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
10、 with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International 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 I
11、nternational Standards adopted by the technical committees are 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. Attention is drawn to the possibility that some of the elements of this document
12、 may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 706 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 fourth edi
13、tion cancels and replaces the third edition (ISO 706:1985), Clauses 6 and 8 of which have been technically revised. In addition, a precision statement and an informative annex concerning the applicability of the standard have been added. BSISO706:2004blank BSISO706:2004ANRETNIITOTS LANDNADRA OSI 074
14、002:6)E(1 Rubber latex Determination of coagulum content (sieve residue) WARNING Persons using this International Standard should be familiar with normal laboratory practice. This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibili
15、ty of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions. 1S c o p e This International Standard specifies a method for the determination of the coagulum content (sieve residue) of natural rubber latex concentrate and the ma
16、jority of synthetic rubber latices. It is not suitable for XSBR latices intended for use in paper coating (see Annex A). 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated
17、 references, the latest edition of the referenced document (including any amendments) applies. ISO 123, Rubber latex Sampling ISO 3310-1, Test sieves Technical requirements and testing Part 1: Test sieves of metal wire cloth ISO 4576, Plastics Polymer dispersions Determination of sieve residue (gros
18、s particle and coagulum content) ISO/TR 9272, Rubber and rubber products Determination of precision for test method standards 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 laboratory sample a quantity of latex intended for laboratory inspec
19、tion and testing that is representative of the lot 3.2 coagulum content sieve residue material, comprising foreign matter and flocculated rubber, retained under the conditions of the test on a stainless-steel wire cloth with an average aperture width of , complying with ISO 3310-1 NOTE In the contex
20、t of the examination of rubber shipments, bulk deliveries, etc., this is what is generally understood by “coagulum”. Pieces of latex skin and gross pieces of coagulated rubber do not constitute part of the laboratory sample and are removed by the initial straining. 180 m 10 m BSISO706:2004ISO :607(4
21、002)E 2 4P r i n c i p l e A portion of the laboratory sample taken from the bulk material is strained through a coarse filter and then mixed with surfactant and strained through a wire cloth of defined mesh. The coagulum content is determined by drying the residue after washing free from latex. 5R
22、e a g e n t s During the analysis, use only reagents of recognized analytical grade and only distilled water or water of equivalent purity. 5.1 Anionic surfactant, consisting of a solution of potassium oleate or ammonium laurate containing of surfactant/ of solution (for use with natural rubber lati
23、ces). 5.2 Non-ionic surfactant, consisting of a solution of water-soluble ethoxylated alkylphenol containing of surfactant/ of solution and having a pH of (for use with synthetic rubber latices). 5.3 Indicator paper. 6 Apparatus Standard laboratory apparatus, plus the following: 6.1 Filter, consisti
24、ng of a sieve with a nominal aperture of , made of stainless-steel wire or synthetic-fibre cloth, resistant to latex. 6.2 Test filter, consisting of a disc of stainless-steel wire cloth (preferred material), with a nominal aperture of , complying with ISO 3310-1. Synthetic-fibre cloth may also be us
25、ed. If the filter requires cleaning (e.g. for re-use), immerse it in cold (by volume) nitric acid and boil for . Wash well with water and dry to constant mass. WARNING This must not be done with synthetic-fibre cloth. 6.3 Two stainless-steel rings, of equal internal diameter between and 6.4 Beakers,
26、 of capacity , with a lip. 6.5 Oven, capable of being maintained at (see, however, the Note to 8.6). 6.6 Desiccator. 6.7 Balances: an analytical balance capable of weighing to an accuracy of or better and a balance capable of weighing to an accuracy of . 7 Sampling Prepare a laboratory sample in acc
27、ordance with one of the methods specified in ISO 123. The laboratory sample shall not include any pieces of dried latex skin or any gross pieces of coagulated rubber. 8 Procedure 8.1 Carry out the test in duplicate, as follows. 8.2 Thoroughly stir the laboratory sample to ensure that it is homogeneo
28、us. 50 g dm 3 50 g dm 3 7,0 0,5 710 m 25 m 180 m 10 m 5 % 30 min 25 mm 50 mm 600 cm 3 100 C 5 C 1mg 1g BSISO706:2004OSI 7064002:)E(3 8.3 Strain an adequate quantity of the laboratory sample through the filter (6.1) into a clean beaker (6.4). Cover the beaker to ensure that there is no surface drying
29、 of the latex. 8.4 Dry the test filter (6.2) to constant mass in the oven (6.5) at (see Note to 8.6) and record the mass to the nearest ( ). Firmly clamp the test filter between the stainless-steel rings (6.3). Weigh, to the nearest gram, ( ) of the strained laboratory sample prepared in 8.3 into a
30、beaker (6.4). Mix thoroughly while adding of anionic surfactant solution (5.1) in the case of natural rubber latex concentrate or of non-ionic surfactant solution (5.2) in the case of synthetic rubber latex. Wet the clamped test filter (6.2) with the surfactant solution used (5.1 or 5.2), then pour
31、the latex/surfactant mixture through it. Without delay, rinse out the beaker with a small amount of the surfactant solution, pouring the washings through the filter. Continue to wash the residue on the filter with small amounts of surfactant solution until the washings are clear and free of latex. W
32、ith natural rubber latex, continue to wash the residue with water until the washings are neutral to indicator paper (5.3). With synthetic rubber latex, wash the residue with a further of water. 8.5 Carefully remove the filter containing the wet coagulum from the clamp and blot the underside with fil
33、ter paper. 8.6 Dry the filter and coagulum for in the oven at (see Note), transfer to the desiccator (6.6) and allow to cool. Weigh to the nearest . Return to the oven at (see Note) for a further period of , allow to cool in the desiccator and weigh as before. Repeat the drying period until the loss
34、 in mass between successive weighings is less than . Record the mass of the dried filter and coagulum () . NOTE Other drying temperatures may be used if considered suitable (see ISO 4576). 9 Expression of results The coagulum content, expressed as a percentage by mass of the latex, is given by the e
35、quation: whereis the mass, in grams, of the test portion; is the mass, in grams, of the test filter; is the mass, in grams, of the test filter plus dried coagulum. Report the mean of the duplicate determinations. If the individual results differ from the mean by more than 0,001 units, repeat the det
36、ermination. 10 Precision 10.1 The precision of this method was determined in accordance with ISO/TR 9272. Refer to this document for terminology and other statistical details. 10.2 The precision data are given in Table 1. The precision parameters shall not be used for acceptance or rejection of any
37、group of materials without documentation that the parameters are applicable to those particular materials and specific test protocols of the test method. The precision is expressed on the basis of a confidence level for the values established for repeatability and reproducibility . 710 m 100 C 5 C 1
38、mgm 1 200 g1gm 0 200 cm 3 200 cm 3 200 cm 3 30 min 100 C 5 C 1 mg 100 C 5 C 15 min 15 min 1mg m 2 % coagulum content= m 2 m 1 m 0 100 m 0 m 1 m 2 95 % rR BSISO706:2004ISO :607(4002)E 4 10.3 The results contained in Table 1 are average values and give an estimate of the precision of this test method
39、as determined in an interlaboratory test programme carried out in 2001 and including 13 laboratories performing triplicate analyses on two samples A and B which were prepared from high-ammonia latex. Before the bulk was sub-sampled into bottles labelled A and B, it was filtered and homogenized by th
40、orough stirring. Thus, essentially, samples A and B were the same and were treated as such in the statistical computations. Each participating laboratory was required to carry out the test using these two samples, on the dates given to them. 10.4 A Type 1 precision was evaluated based on the method
41、of sampling used for the interlaboratory test programme. 10.5 Repeatability: The repeatability (in measurement units) of the test method has been established as the appropriate value tabulated in T able 1. Two single test results, obtained in the same laboratory under normal test method procedures,
42、that differ by more than the tabulated (for any given level) shall be considered to have come from different, or non-identical, sample populations. 10.6 Reproducibility: The reproducibility (in measurement units) of the test method has been established as the appropriate value tabulated in Table 1.
43、Two single test results, obtained in different laboratories under normal test method procedures, that differ by more than the tabulated (for any given level) shall be considered to have come from different, or non-identical, sample populations. 10.7 Bias: In test method terminology, bias is the diff
44、erence between an average test value and the reference (or true) test property value. Reference values do not exist for this test method since the value (of the test property) is exclusively defined by the test method. Bias cannot therefore be determined for this particular method. 11 Test report Th
45、e test report shall include the following information: a) a reference to this International Standard; b) all details necessary for the identification of the material tested; c) the mean of the duplicate determinations; d) details of any unusual features noted during the test; Table 1 Precision data
46、Average result Within laboratory Between laboratories 0,001 0,000 4 0,001 0,000 5 0,002 where is the repeatability (in measurement units); is the within-laboratory standard deviation;and where is the reproducibility (in measurement units); is the between-laboratory standard deviation. 1l r r R R s r
47、 rs R R r= 2,83s r r s r R= 2,83s R R s R BSISO706:2004OSI 7064002:)E(5 e) details of any operation not included in this International Standard or in any of the International Standards to which reference is made, together with details of any operation regarded as optional; f) the date of the test. B
48、SISO706:2004ISO :607(4002)E 6 Annex A (informative) Applicability of ISO 706 The method and definitions given in ISO 706 are an integral part of the specifications for natural rubber latex concentrate (ISO 2004 and ISO 2027). They are also appropriate to synthetic latices used, for example, in the m
49、anufacture of foam, dipping rubber and adhesives. Coagulum of a size that would pass ISO 706 would not, however, be acceptable for high-speed coating applications such as are employed in the paper industry. For this purpose, it is necessary that the latex pass a test employing a test filter with an average aperture ofcomplying with ISO 3310-1. At present, the requirements for such latices will have to be the subject of agreement between
