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method for preparing under the direct action of the sunlight biodegradable thermoplastic polymers.and product obtained by application of polymers prepared by the method.
method for preparing under the direct action of the sunlight biodegradable thermoplastic polymers.and product obtained by application of polymers prepared by the method.
1437100 Photodegradable polymers SNAMPROGETTI SpA 31 Dec 1973 [15 Jan 1973] 60193/73 Heading C3P Photodegradable thermoplastics materials comprise a thermoplastic polymer having incorporated therein as prodegradant an olefinically unsaturated compound containing at least two double bonds and of general formula wherein R 1 -R 8 are H, alkyl, aryl, cycloalkyl, aralkyl or alkaryl, or an adjacent pair of radicals is joined to form a ring, optionally containing one or more double bonds which may be conjugated with the double bonds present in said compound, A and B are alkylene, arylene, cycloalkylene, aralkylene or alkarylene, p and q are 0 or 1, n is 0 or 1 to 12 provided that n is 0 if none of R 1 -R 8 is an aryl radical, the materials being free from sulphur-containing compounds having antioxidant effect which would be synergized by the unsaturated compound. Preferred compounds contain conjugated double bonds e.g. 1,6-diphenylhexatriene, 5-phenyl- 1,3 - pentadiene, octa - 2,4,6 - triene, 2,6- dimethyl - octa - 2,46 - triene and 2 - methyl- 1,3,5-hexatriene. The polymer may be polyethylene, polypropylene or an ethylene/vinyl acetate copolymer. Examples describe compositions of 1,6-diphenylhexatriene with (1 and 2) polyethylene, (3) ethylene/vinyl acetate copolymer and (4) polypropylene; and of 2,6-dimethyl-2,4,6-octatriene with (5) polyethylene.
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