in free biodegradable plastic to kohlenwasserstoffbasis

摘要

1385759 Degradable polymer articles DEBELL & RICHARDSON Inc 12 Oct 1972 [23 Aug 1972] 47034/72 Heading C3P Ultra-violet degradable plastic articles of thickness less than 80 mils are made of compositions comprising (a) 100 parts by weight of a hydrocarbon resin which is a homopolymer of propylene, butene-1, isobutylene, pentene-1, 4-methylpentene-1 or hexene-1, or a copolymer thereof with up to 35 weight per cent of ethylene and (b) a sensitizer-promoter of particle size not greater than 3À4 microns and surface area not less than 0À7 m.SP2/SP/gm., selected from (1) oxides of silicon, tin, lead, aluminium, bismuth, antimony and magnesium and fatty and rosin acid dispersions thereof, (2) Group IIa metal, aluminium, bismuth, antimony, tin and lead silicates and Group Ia metal aluminosilicates, (3) barium, strontium, calcium and lead sulphates and bismuth and antimony basic sulphates, (4) Group IIa metal, aluminium, tin, lead, bismuth and antimony carbonates, (5) Group IIa metal, aluminium, tin, lead, bismuth and antimony phosphates, and (6) Group II metal, aluminium, tin, lead, antimony and bismuth salts of oleic, hydroxystearic and C 5-23 alkanoic acids; the sensitizer-promoter of group (6) being present in amount of 0À1 to 5 parts by weight and groups (1) to (5) in amounts from 1 part by weight to a maximum given by the formula 15-17À1 (refractive index -1À7) x (thickness of article in thousandths of an inch)/ 0À02, members of groups (1) to (5) being sufficiently fine to provide a surface area A=10SP2.44/SP (refractive index-1À564) m.SP2/SP/gm. when the refractive index is greater than 1À564. Many suitable materials are listed and examples describe compositions of polypropylene and silica, calcium silicate, aluminium silicate, sodium silicoaluminate, talc, attapulgite clay, wollastonite, alumina, lead chlorosilicate, tribasic lead sulphate, magnesium oxide, antimony trioxide, tin oxide, calcium carbonate, barium sulphate, titanium dioxide, tricalcium phosphate, glass fibre, dispersed asbestos, potassium titanate, calcium stearate, sodium stearate, basic zinc stearate, cadmium stearate, aluminium mono-, di- and tri-stearate, aluminium trioleate, aluminium octoate, dibasic lead stearate and aluminium 12-hydroxystearate; and of silica with ethylene/propylene block copolymer, polybutene-1 and poly-4-methylpentene-1.