without additive control thus for example polystyrene containing n bromosuccinimide is oxidized photochemically 1 065 176 or 6 1 times more than polystyrene without an additive to 0 6 gram of powdered polyethylene resin was added a solution of 0 006 gram of n bromosuccinimide in 0 6 ml of acetone the mixture was stirred to evenly distribute the additive solution over the particles of polyethylene the mixture was spread as a thin layer on a mylar sheet supported by a ferrotype chrome plate after allowing the acetone to evaporate the said layer was covered with another mylar sheet and chrome plate this assembly was heated for 30 seconds at 350 u00b0 f and then pressed at 370 psi for 30 seconds the assembly was then transferred to an unheated press and pressed at 4 000 psi while cooling a film of polyethylene and 1 added n bromosuccinimide having a thickness of 0 003 to 0 004 inch was thus obtained a similar procedure was employed for the preparation of polyethylene films containing other additives the temperature of the heated press was varied from 350 u00b0 412 u00b0 f depending on the melting point of the additive in general the temperature of the press was about 10 u00b0 f above the melting point of the additive samples of the polyethylene additive film and control polyethylene film without any additive were tested for photodegradability as described in example 1.