Thermal peroxidized PP films and PE films were graft copolymerized with a light stabilizer
2
2
6
6-tera-methyl-piperidinyl-merhacrylate (MTMP)
by UV-irradiation in the absence of sensitizers in order to improve the photostability of films. The influence of various factors
including the thermal peroxidizing time
irradiation time
monomer concentration and the type of solvents
on the grafting content of the peroxidized films was examined. It is shown that the graft copolymerization can not take place in common organic solvents except ketones
and the photostability of either grafted PP or grafted PE film increases greatly com-pared with that of the ungrafted film.