A quaternary ammonium salt (QAS)

Methacryloxylethfl benzyl dimethyl ammonium chloride

was introduced onto the surface of PE films by UV photografting technique．The photografted films were characterized by FTIR．XPS and SEM．Morphology of the grafted layers were studied and was found to change with th UV Light irradimion time．The PE film surfaces were uniformly covered with the QAS moieties and the thickness was about several μm．A clear boundary between the grafted layer and the substrate surface was also observed．