PHOTODEGRADABLE HYDROCARBON POLYMERS

摘要

1478885 Photodegradable polymer compositions BIO-DEGRADABLE PLASTICS Inc 11 June 1974 [21 June 1973] 25886/74 Addition to 1385497 Heading C3P Material which is photodegradable on exposure to the ultraviolet content of sunlight in an atmospheric environment comprises a hydrocarbon polymer which is polyethylene, polystyrene or rubber-modified polystyrene and a photosensitizing agent selected from 4,41-di-t.- butylbenzophenone, 4 - t - butylbenzophenone and compounds of formulae where R 3 and R 4 are H, halogen, alkyl or alkoxy, R 5 and R 6 are H, hydroxyl, alkyl or alkoxy, R 7 is H, halogen, alkyl or alkoxy and X is carbonyl or CHR 8 where R 8 is H, alkyl or alkoxy. The polyethylene may also contain a transition metal salt, e.g. manganese or iron stearate, or a degradation enhancing pigment. Examples describe compositions of high impact polystyrene with 4,41-di-t. butyl and 4-t. butylbenzophenones, anthrone and 4-hydroxy-3-methoxybenzaldehyde, and of polyethylene with 4,41- di-t. butylbenzophenone with and without iron stearate and optionally iron oxide pigment.