GB1434641A - Thermoplastic polyolefin compositions with controlled degra dability - Google Patents

Abstract

1434641 Degradable polyolefin compositions CHEMISCHE WERKE HULS AG 19 Sept 1973 [20 Sept 1972] 43908/73 Heading C3P Thermoplastic compositions of controlled degradability comprise relative to the polyolefin (a) 0À01 to 1 weight per cent of an antioxidant, (b) 0À02 to 1 weight per cent of an organic copper salt, (c) 0À1 to 2 weight per cent of an organic manganese, cobalt or iron salt, (d) 0À01 to 0À4 weight per cent of a peroxide, (e) 0À02 to 3 weight per cent of a ketone and optionally (f) 1 to 10 weight per cent of an optionally epoxidized hydrocarbon oil, carboxylic acid ester or carboxylic acid amide. The polyolefin may be a polymer or copolymer of ethylene, propylene or butene-1. The antioxidant may be a hindered phenol. The copper, manganese, cobalt and iron salts may be resinates, naphthenates, oleates, palmitates, stearates and octoates. The peroxide may be cumene, benzoyl, propyl, t-butyl, cyclohexyl, barium or potassium peroxide. Preferably a mixture of a peroxide which decomposes at polymer processing temperatures with a peroxide which is stable at such temperatures is used. The ketone may be benzophenone, benzoin, 2,4-dimethyl benzophenone, o-dibenzoyl benzene or a hydroxyketone of melting point above 250‹ C. The epoxidized oil may be an epoxidized polyethylene or polybutadiene, or an epoxidized vegetable oil. The compositions may also contain light stabilizers, reducing agents such as disodium phosphite and calcium sulphite, and fillers such as kaolin, clay and diatomaceous earth. The compositions may be subject to silent electric discharges, e.g. corona discharges. Examples describe compositions of polybutene-1, polypropylene and polyethylene.