Effect of interface modification on the photo-stability of pigmented polyethylene films

The deterioration of differently stabilised and pigmented high density poly ethylene films was investigated by DSC and UV spectroscopy methods in the c ourse of accelerated photo-ageing and compared to earlier XPS and gel-conte nt results. Unexpectedly quick destruction of phthalocyanine containing him was observed and explained by the adsorptive removal of the stabiliser fro m the polymer matrix. In the pigment (filler)-solvent-stabiliser model syst ems the high susceptibility of hindered phenol type heat-stabiliser to adso rb on talc and phthalocyanine pigment was proved by UV spectroscopic measur ements. Surface coating of the talc and pigment with a reactive surfactant considerable reduced the adsorption capacity and thus improved the photo-st ability of the pigmented film. (C) 2001 Elsevier Science Ltd. All rights re served.