1、BRITISH STANDARD BS1524:1993 Specification for Cellulose acetate moulding materialsBS1524:1993 This British Standard, having been prepared under the directionof the Plastics and RubberStandards Policy Committee, was published underthe authority of the Standards Board and comes intoeffect on 15Februa
2、ry1993 BSI11-1999 First published February1949 Second edition April1955 Third edition February1993 The following BSI references relate to the work on this standard: Committee referencePRM/30 Draft for approval92/35958 ISBN 0 580 21484 2 Committees responsible for this British Standard The preparatio
3、n of this British Standard was entrusted by the Plastics and Rubber Standards Policy Committee (PRM/-) to Technical Committee PRM/30, upon which the following bodies were represented: American National Standards Institute British Plastics Federation Ministry of Defence Standards Association of Austr
4、alia Amendments issued since publication Amd. No. Date CommentsBS1524:1993 BSI 11-1999 i Contents Page Committees responsible Inside front cover Foreword ii 1 Scope 1 2 Normative references 1 3 Definitions 1 4 Grades 1 5 Requirements to be agreed and to be documented 1 6 Sampling 1 7 Test specimen p
5、reparation and conditioning 1 8 Fines and impurities 1 9 Properties 2 10 Marking 3 Annex A (normative) Procedure for the preparation of specimens for test 4 Annex B (normative) Conditioning 4 Annex C (normative) Determination of moisture content 4 Annex D (normative) Determination of viscosity chang
6、e on moulding 6 Annex E (normative) Determination of loss in mass by heating 6 Figure A.1 Mould 5 Table 1 Comparison of old and new grades ii Table 2 Property requirements 3 List of references Inside back coverBS1524:1993 ii BSI 11-1999 Foreword This British Standard has been prepared under the dire
7、ction of the Plastics and Rubber Standards Policy Committee. It supersedes BS1524:1955, which is withdrawn. In this edition the different materials have been graded according to their melt flow rate and test methods updated to align where possible with the corresponding ISO methods. Although the cor
8、respondence is not precise, an indication of how the new grades compare to those of the1955edition has been given in Table 1. Table 1 Comparison of old and new grades A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible
9、 for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Material description Grades in the1955 edition Grades in this edition Very soft S6,S5,S4 A Soft S3,S2, S B Medium M2, M, MH C Hard H, H2,H3 D Very hard H4,H5,H6 E Summary of
10、pages This document comprises a front cover, an inside front cover, pagesi andii, pages1 to6, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.B
11、S1524:1993 BSI 11-1999 1 1 Scope This British Standard specifies the requirements for cellulose acetate moulding materials. In addition to the definitive requirements, this standard also requires the items detailed in clause4 to be documented. For compliance with this standard, both the definitive r
12、equirements and documented items have to be satisfied. 2 Normative references This British Standard incorporates, by reference, provisions from specific editions of other publications. These normative references are cited at the appropriate points in the text and the publications are listed on the i
13、nside back cover. Subsequent amendments to, or revisions of, any of these publications apply to this British Standard only when incorporated in it by updating or revision. 3 Definitions For the purposes of this British Standard, the following definitions apply. 3.1 cellulose acetate an acetic acid e
14、ster of cellulose (excluding mixed esters) 3.2 cellulose acetate moulding material a thermoplastic composition in granular form capable of being shaped by heat and pressure, and consisting of cellulose acetate compounded with one or more plasticizers and small proportions of other ingredients 4 Grad
15、es The material shall be graded into five grades, AtoE, according to their melt flow rate, stiffness and impact strength (see clause9 and Table 2). 5 Requirements to be agreed and to be documented 5.1 Information to be supplied by the purchaser The following items to be agreed between the contractin
16、g parties, which are specified in the clauses referred to, shall be fully documented. Both the definitive requirements specified throughout the standard and the following documented items shall be satisfied before a claim of compliance with the standard can be made and verified: a) the preparation a
17、nd storage of sheet test specimens (see clause7); b) the conditioning of test specimens (seeclause7); c) the level of impurities (see8.2); d) for grades A and E, the melt flow rate (see9.1.2); e) for grade A, the impact strength(see9.3.2); f) for grades A and E, the tensile strength(see9.4.2); g) fo
18、r grades A and E, the temperature of deflection under a bending stress of1.8MPa(see9.5.2); h) for grades A and E, the moisture absorption(see9.7.2); i) for grades A and E, the loss in mass by leaching(see9.8.2); j) for grades A and E, the loss in mass by heating(see9.9.2). 5.2 Options If the purchas
19、er wishes to take up any of the optional requirements given in this standard(see9.11 and9.12), such requirements shall be specified and documented at the time of the enquiry and/or order. In the absence of such information, the manufacturer shall supply in accordance with the basic specification. 6
20、Sampling A representative sample weighing approximately2kg shall be used. 7 Test specimen preparation and conditioning When sheet test specimens are required they shall be prepared and stored either in accordance with Annex A or as agreed between purchaser and manufacturer. Conditioning shall be car
21、ried out either in accordance with the procedure given in Annex B or as agreed between purchaser and manufacturer. 8 Fines and impurities 8.1 Not more than5% of the material shall pass through an850m aperture test sieve conforming to BS410:1986. 8.2 The level of solid impurities shall be as specifie
22、d by the purchaser.BS1524:1993 2 BSI 11-1999 9 Properties 9.1 Melt flow rate 9.1.1 Grades B, C and D The melt flow rate for grades B, C and D shall conform to the applicable value given in Table 2, when tested as follows. Dry a specimen of the polymer sample by maintaining it at80 C for1.5h and then
23、 allowing it to cool in a desiccator over silica gel for a period of15min to45min. Test in accordance with condition8 given in Table2 of BS2782:Method720A:1979. 9.1.2 Grades A and E When tested in accordance with9.1.1, the melt flow rate for grades A and E shall conform to the applicable value given
24、 in Table 2, but the specific value shall be specified by the purchaser. 9.2 Moisture content The moisture content at the time of despatch shall not exceed0.5% when tested in accordance with Annex C. NOTEMoulding material conforming to this clause is not necessarily suitable for use without predryin
25、g. A procedure is described in Annex A. 9.3 Impact strength 9.3.1 Grades B, C, D and E The impact strength for grades B, C, D and E shall conform to the applicable value given in Table 2 when tested in accordance with BS2782:Method350:1984, using specimen3 with notch A as specified in Table2 and Tab
26、le3 of BS2782:Method350:1984. 9.3.2 Grade A The impact strength for grade A shall conform to the value specified by the purchaser when tested in accordance with BS2782:Method350:1984, using specimen3 with notch A as specified in Table2 and Table3 of BS2782:Method350:1984. 9.4 Tensile strength 9.4.1
27、Grades B, C and D The tensile strength for grades B, C and D shall conform to the applicable value given in Table 2 when tested in accordance with method320C of BS2782:Methods320A to320F:1976. 9.4.2 Grades A and E The tensile strength for grades A and E shall conform to the value specified by the pu
28、rchaser when tested in accordance with method320C of BS2782:Methods320A to320F:1976. 9.5 Temperature of deflection under a bending stress of1.8MPa 9.5.1 Grades B, C and D The deflection under load for grades B, C and D shall conform to the applicable value given in Table 2 when tested in accordance
29、with method121A of BS2782:Methods121A and121B:1991, using test specimens prepared in accordance with Annex A and conditioned in accordance with Annex B. 9.5.2 Grades A and E The deflection under load for grades A and E shall conform to the value specified by the purchaser when tested in accordance w
30、ith method121A of BS2782:Methods121A and121B:1991, using test specimens prepared in accordance with Annex A and conditioned in accordance with Annex B. 9.6 Viscosity change on moulding The viscosity change on moulding shall conform to the applicable value given in Table 2 when tested in accordance w
31、ith Annex D. 9.7 Moisture absorption 9.7.1 Grades B, C and D The moisture absorption for grades B, C and D shall conform to the applicable value given in Table 2 when a3mm thick sheet is tested in accordance with method430A of BS2782:Methods430A to430D:1983. 9.7.2 Grades A and E The moisture absorpt
32、ion for grades A and E shall conform to the value specified by the purchaser when a3mm thick sheet is tested in accordance with method430A of BS2782:Methods430A to430D:1983. 9.8 Loss in mass by leaching 9.8.1 Grades B, C and D The loss in mass by leaching for grades B, C and D shall conform to the a
33、pplicable value given in Table 2 when a3mm thick sheet is tested in accordance with method430B of BS2782:Methods430A to430D:1983. 9.8.2 Grades A and E The loss in mass by leaching for grades A and E shall conform to the value specified by the purchaser when a3mm thick sheet is tested in accordance w
34、ith method430B of BS2782:Methods430A to430D:1983.BS1524:1993 BSI 11-1999 3 9.9 Loss in mass by heating 9.9.1 Grades B, C and D The loss in mass by heating for grades B, C and D shall conform to the applicable value given in Table 2 when tested in accordance with Annex E. 9.9.2 Grades A and E The los
35、s in mass by heating for grades A and E shall conform to the value specified by the purchaser when tested in accordance with Annex E. 9.10 Burning behaviour of150mm 13mm test specimens The average rate of burning of three specimens shall not exceed75mm/min when tested in accordance with method A of
36、BS2872:Method140A:1992. 9.11 Colour fastness to light NOTEThis option may be agreed at the time of enquiry and/or order. If required by the purchaser, the colour fastness to light when tested in accordance with BS2782:Method540B:1982 shall conform to the value specified by the purchaser. 9.12 Vicat
37、softening temperature NOTEThis option may be agreed at the time of enquiry and/or order. If required by the purchaser, the Vicat softening temperature when tested in accordance with BS2782:Method120C:1990 shall conform to the value specified by the purchaser. 10 Marking Material containers shall be
38、marked with at least the following information: a) the number and date of this British Standard i.e.BS1524:1993 1) ; b) the grade of material (see clause5 and Table 2); c) the name or trade mark of the supplier. For example, a grade B material manufactured by A bring the contents to boiling point an
39、d continue boiling for45min. Push any drops of water which remain in the condenser into the receiver with a glass rod before boiling is stopped. Allow the apparatus to cool for10min and read the volume of water in the receiver. Calculate the percentage moisture content of the material from the following equation: percentage moisture content where V is the volume of water (in ml) in the receiver at the end of the determination; W is the mass (in g) of the moulding material. V 100 W - =
