1、 BSI BS*3012 70 162qbb 0074931 I W SPECIFICATION FOR LOW AND INTERMEDIATE DENSITY POLYTHENE SHEET FOR GENERAL PURPOSES BS 3012:1970 BRITISH STANDARDS INSTITUTION INCORPORATED BY ROYAL CHARTER 2 PARK STREET, LONDON W1A 2BS Telex : 266933 Telephone : 01-629 9000 BSI BS*3032 70 E 3624667 0074932 3 BS 3
2、012 : 1970 THIS BRITISH STANDARD, having been approved by the Plastics Industry Standards Committee, was published under the authority of the Executive Board on 30 November, 1970. O British Standards Institution, 1970. First published August, 1958. First revision November, 1970. SBN: 580 06424 7 The
3、 Institution desires to cdl attention to the fact #that this British Standard does not purport to include all the neces- sary provisions of a contract. In order to keep abreast of progress in the industries concerned, British Standards are subject to periodical review. Suggestions for improvements w
4、ill be recorded and in due course brought to the notice of the committees charged with the revision of ,the standards to which they refer, A complete list of British Standards, numbering over 5000, fully indexed and with a note of the contents of each, will be found in the British Standards Yearbook
5、, price El. The BS Yearbook may be consulted in many public libraries and similar institutions. This standard makes reference to the following British Standards : BS 572. Interchangeable conical ground glass joints BS 1792. One-mark volumetric flasks BS 1972. Polythene pipe Fype 32) for cold water s
6、ervices BS 1973. Polythene pipe (Type 32) for general purposes including chemical and food industry uses BS 2660. Colours for building and decorative parts BS 2746. PVC insulation and sheath for electric cables BS 2782. Methods of testing plastics BS 2919. Low and intermediate density polythene rod
7、for general purposes BS 3978. Water for laboratory use BS 4646. High density polythene sheet for general purposes. British Standards are revised, when necessary, by the issue either of amendment slips or of revised editions. It is important that users of British Standards should ascertain that they
8、are in possession of the latest amendments or editions. The following BSI references relate to the work on this standard: Committee references PLC/9 and PLC/9/3 Draft for comment 67/29598 2 BSI BS*3012 70 I lb24bb 0074933 5 BS 3012 : 1970 CONTENTS Co-operating organizations Foreword SPECIFICATION 1.
9、 Scope 2. Composition 3. e Resin Manufacturers Association The Government departments and scientific and industrial organizations marked with an asterisk in the above list, together with the following, were directly remesenteci on the committee entrusted with the preparation of this Britiih S-tandar
10、d : Agrment Board Associated Master Plumbers and Domestic Engineers Association of Industrialized Building Component Manufacturers Ltd. Association of Public Health Inspectors British Chemical Plant Manufacturers Association Bnitisli Mechanical Rubber Manufacturers Association British Rubber Manufac
11、turers Associadon Ltd. British Waterworks Association Chemical Industries Association Copper Tube Fittings Mpufacturers Association Dai Engineers Association Fooa) Manufacturers Federation Unc.) Gas Council Gas List Tube Association Greater London Council Institute of Plumbing Institut,on of Civil E
12、ngineers Institution of Municipal Engineers Institution of Public Health Engineers Institution of Water Engineers Lloyds Register of Sliipphg Milk Distributive Council Ministry of Agriculture Fisheries and Food Ministry of Housing aid Local Government Ministry of Public Building and Works National C
13、oal Board National Federation of Plumbers and Dome: National Institute for Research in Dairying Plastic Pipe Manufacturers Spolety Royal Society.for the Promotion of Health Society of Builders Merchaqts Water Companies Association Water Research Association Institute of Brewing 4 rtic Heating Engine
14、ers BSI BS*3012 70 W Lb24bb9 0074935 9 W BS 3012 : 1970 BRITISH STANDARD SPECIFICATION FOR LOW AND INTERMEDIATE DENSITY POLYTHENE SHEET FOR GENERAL PURPOSES FOREWORD This British Standard has been prepared under the authority of the Plastics Industry Standards Committee to meet the needs of industry
15、 for polythene sheet for use in welded fabrications incorporating low density polythene pipe (BS 1972* and 1973Jy), and low and intermediafe density polythene rod (BS 2919%) and for other purposes. It is based on a draft prepared by the British Plastics Federation. This British Standard was frst pub
16、lished in 1958. In the present revision the requirements in respect of composition have been changed to bring them into line as far as possible with those in BS 1972* and 1973Jy. The opportunity has been taken to express dimensions in metric unh. However, to avoid possilble confusion during the peri
17、od of transition to fuil metric thinking it has been decided that the nominal thickness should be designated using the nominal thickness correspondhg to the old values in inches. A specification for high density polythene sheet is provided in BS 46460. Throughout this standard the name pulythene is
18、used. It should be noted that this name is equivalent to the name polyethylene . * BS 1W2, Polythene pipe (Type 32) for cold water services. t BS 1W3, Polythene pipe (Type 425) for general purposes including chemical and food industry uses, 8 BS 4646, High density polythene sheet for general purpose
19、s. BS 2919, Low and intermediate density polythene rod. 5 BSI BS*30l12 70 m Lb24bb 007493b O m BS 3012 : 1970 SPECIFICATION 1. SCOPE This British Standard specifies requirements for low and intermediate density polythene sheet of nominal thickness not less than 0.5 mm for general purposes including
20、pipe fabrication, chemical, food and building industry uses. Additionally the spedific requirements for pink and brown sheet for external surgical appliances (splints) are stated. 2. COMPOSITION 2.1 Coinpound 2.1.1 The compound used for the manufacture of the sheet shall consist of polythene with a
21、density not greater than 0.93 g/mi at 20 “C. 2.1.2 For general purpose applications the polythene shall have a melt flow index between 0.1 and 8.0 when tested by Method 10% of BS 2782*. For use in conjunction with polythene pipe complying with BS 19721. or 1973F, or with polythehe rod complying with
22、 BS 29198, the polythene shail be within one of the three following grades, the melt flow index being determined by Method 105C of BS 2782*. (1) Grade X having a melt flow index of 0-21 to 0.49, and a density not (2) Grade Y having a melt flow index of 0.50 to 1.19, and a density not (3) Grade Z hav
23、ing a melt flow index of 1.20 to 25, and a density not NOTE. When used in conjunction with pipe and rod it is essential that the giade of material for the sheet matches in all respects that for the pipe or rod with which it is being used. 2.13 Black compound shall consist of polythene in any one of
24、the grades defined in 2.1.2, in which the foliowing Ingredients shall be uniformly dispersed : (i) Carbon black in such amount that when the compound is tested by Method 405A of BS 2782*, the carbon black content shall be The carbon black shall comply with the following requirements : a. Density : 1
25、.5-2.0 g/ml. greater than 0,930. greater than 0.928. greater than 0,924. 2.5 -1- 0.5 %. * BS 2782, Methods of testing plastics. t BS 1W2, Polythene pipe (Type 32) for cold water services. $ BS 1973, Polythene pipe (Type 425) for general purposes including chemical and food industry uses. BS 2919, Lo
26、w and intermediate density polythene. 6 (2) NOTE, b. n. c. BS 3012 : 1970 Maxiniurn volatile matter: 9.0 % by mass. Average particle size : 0.010-0*025 pm. Tolueize extract : not more than 0.10 % by mass when determined by the method described in Appendix A. Antioxidant, in such amount that, when th
27、e compound is tested by Method 405B of BS 27S2“ or by the method described in the appro- priate appendix to this standard the antioxidant content shall not be more than 0.30 % by mass, The antioxidant shall be one of the following: (1. I * C. (l. . NN-di-2-naphthyl-p-phenylenediaminel with a melting
28、 range of 328 “C to 235 “C (Method 405B of BS 2782). 3, 4-thiodi-(6-errbutyl-r1t-cresol) (Appendix B). di- 2- hydroxy-5-methyl-3 -( 1 -methylcyclohexyl)phenyl-methane. (Appendix C). 3.6-ditercbutyl-p-cresol (Appendix D). 1,1,3-tri-(5-etbutyl-3-hydroxy-2-methylphenyl)-butane (Appendix E). I Extrusion
29、 compound conforming to Type VA of BS 3412 Polythene materials for moulding and extrusion satisfies the requirements of this standard in respect of carbon black content and average particle size of the carbon black, and content of the permitted antioxidants. 2.1.4 Natural compound shall consist only
30、 of polythene. By contractual agreement between the supplier and the vendor, however, any of the anti- oxidants listed above may be added in the quantities agreed. KOTE. The addition of antioxidants may Icad to slight staining of the natural material but does not otherwise impair its properties. 2.2
31、 Sheet material 2.2.1 Blrick. The sheet shall contain 3.5 * 0-5 % by mass of carbon black when tested by Method 405A of BS 27S3*. The carbon black dispersion shall be satisfactow when tested by Method SlOA of BS 2782*. Figs. 1 to G illustrate satisfactory dispersion and Figs. 7 to 12 illustrate unsa
32、tisEactory dispersion. The antioxidant content of the sheet shall be not less than 0.02 76 by mass when tested by Method 405B of BS 2782“ or by the method described in the appropriate appendix -to this standard. 2.2.2 Notzrrcil. The sheet shall contain only polythene. When, by contrac- tual agreemen
33、t between one purchaser and the vendor, antioxidant is required, the antioxidant content of the sheet shall be not less than 0.02 % by mass when tested by Method 405B of BS 2782“ or by the method described in the appropriate appendix to this standard. 2; BS 2752, hfethods of testing plastics. - 7 BS
34、I BSUOl2 70 lb24bb9 0074938 4 R BS 3012 : 1970 2.23 Pink. The sheet shall contain only polythene to which shall be added sufficient cadmium sulphoselenide and/or cadmium sulphide pigment, with or without the addition of barium sulphate, to conform approximately to colour 2-030 of .BS 2660* and not m
35、ore than 0.1 % by mass of 2,2-bis-(3- rnethyl-4-hydroxyphenyl)-propane when tested by the method described in Appendix For not more than 0.1% by mass of 1,1,3-tri-(5-tertbutyl-+ .hYdroxY-2-. rnethy1plienyl)butane when tested by the method. described in Appendix E.: 2.2.4 Brown. The sheet shall conta
36、in only pofythene to which shall be addtd sufficient cadmium sulphodenick and/or cadmium sulphide pigment, with or without the addition of barium sulphate, and carbon black to conform approximately to the colour brown in Appendix A of BS 2746: 196t and not more than 0.1 % by mass of 2,2-bis-(3-methy
37、l-4-hydroxy- phcnyl)-propanc when tested by the method described in Appendix For not more than 0*1% bv mass of 1,1,3-tri-(5-terfbutyi-4-hydroxy-2- ,methYlPhenYl)butane when tested by the method described in Appendix E: _. NOTE. These antioxidants have been subjected to toxicity tests and have been f
38、ound suitable for use in polythenc sheet for external surgical .appliances. Polythene sheet shall be supplied in one of the following colours : 3. COLOUR (1) Black for general use, and essential where the sheet may be exposed (2) Nafural for use where the sheet will not be exposed to direct sunlight
39、. (3) Prtk for external surgical appliances (splints) only. (4) Brown Ifor external surgical appliances (splints) only. to direct sunlight. 4. FREEDOM FROM DEFECTS .- The sheet shall be reasonably free from surface blemishes and contamina- tion, air bubbles, blisters and voids, and shall be su!bstan
40、tiaiiy uniform in colour. 5. DIMENSIONS 5.1 Where applicable, the thickness of the shed shall be one of those specified in Table 1 and shall conform to the appropriate tolerance specified therein, when measured .by the method described in Appendix G. 5.2 The sheet shall be supplied in square or rect
41、angular shape with clean cut edges. The difference in length of the diagonals drawn across the face of the sheet shall not be greater than 0.5 % except for sheet with an area less than 0.4 m2 for which the maximum difference in length of diagonals shall be agreed between the purchaser and the vendor
42、. The requirements of this olause shall not apply to sheet in roll form. * BS 2660, Colours for building and decorative paints. t BS 2746, PVC insulation and sheath of electric cables. 8 -. / BSI BSx3012 70 9 lb24bb9 0074937 ia 9 BS 3012 : 1970 53 The tolerance on length and width shall be T 2 mm ex
43、cept that for sheet in roll form the tolerance shall be agreed between the purchaser and the vendor. TABLE 1. SHEET )DIMENSIONS Nominal thickness 1 Thickness limits 0:ozo to 01060 Nominal thickness k 10 % - I min. mas. mm mni 1 *4 1.8 2.8 3 *4 4.3 5.0 5.7 6.4 8.8 9.5 # is 4 f 11.7 127 I I 14.6 15.9
44、.) 17.3 19.1 3 the elongation at ,break shall be not less than 350 %. These properties shall (be determined by Method 301F. of BS 2782*, the test specimen having been stamped, cut or machined from the sheet. 7. HEAT REVERSION The diameter of a disc of approximately 50 mm diameter cut from the sheet
45、shall not alter by more than 5 % (for nominal thicknesses up to or by more than 3 % (for nominal thicknesses greater than 2s) when immersed in boiling water for 30 minutes and allowed to cool. 8. MARZUNG 8.1 Each sheet or package of sheets shall be durably marked by means of a strongly adhesive colo
46、ured tape or a suitably painted or stamped mark. The marking shall show in the order stated, manufacturers identity, the number of this British Sfandard, Le. BS 3012 and where appropriate, the grade. 8.2 The marking shall be in green. NOTE. Attention is drawn to certification facilities offered by B
47、SI; see the back cover of this standard. * BS 2782, Methods of testing plastics. 9 -. - - BSI BSX3OL2 70 LbZ4bb 0074940 2 BS 3012 : 1970 APPENDIX A METHOD FOR THE DETERMINATION OF TOLUENE EXTRACT OF CARBON BLACK A.l Apparatus (1) Extraction thimbles, double thickness, fat extracted. (2) Soxhlet appa
48、ratus. (3) Shallow weighing dish, 50 ml capacity, of borosilicate glass. A.2 Reagent. The reagent used shall be of a recognized analytical reagent quality. A3 Procedure. Place 5-8 g of pelletized carbon black or 2-5 g of com- pressed fluffy black in a paper extraction thimble. insert the thimble int
49、o the Soxhlet extractor. Measure 50-60 ml of toluene into the Soxhlet flask. Toluene, sulphur-free. Assemble the Soxhlet apparatus and extract for 22 h. Evaporate successive small portions of the extract solution (filtered if necessary) nearly to dryness in the previously cleaned, dried and tared 50 ml shallow glass weighing dish. Rinse the extraction flask with toluene and add the washings to the weighing dish. Evaporate the combined extracts on a hotplate to a volume of approximately 5-10 ml, and finally dry the dish an
