| 摘要 |
1401418 Degradable thermoplastics compositions IMPERIAL CHEMICAL INDUSTRIES Ltd 27 Oct 1972 [24 Nov 1971] 54566/71 Heading C3P Degradable thermoplastics compositions comprise 0À001 to 40 weight per cent of prodegradant comprising (1) a free carboxylic acid of formula RCOOH where R is a hydrocarbon group with up to 30 C atoms and (2) a carboxylic acid salt of a metal of atomic number 22-29, present in such proportions that the free acid constitutes 10 to 95 per cent of the weight of acid and salt. Specified thermoplastics are polymers of ethylene, propylene, butene-1, 4-methylpentene- 1 and/or styrene, optionally together with vinyl chloride, vinyl acetate, methyl acrylate, methyl methacrylate, acrylic acid, methacrylic acid or hydroxyethyl methacrylate. Examples describe compositions comprising polyethylene, ferric stearate, stearic acid and optionally 2,6-di-t-butyl-4-methylphenol, or benzoic, pelargonic, lauric, oleic, linoleic or behenic acid; comprising polyethylene, manganese stearate and stearic acid; and comprising ethylene/vinyl acetate copolymer, polypropylene stabilized with calcium stearate and 2,6-di-t-butyl-4-methylphenol or ethylene/ methacrylic ionomer resin together with ferric stearate and stearic acid. |
