PLASMA SURFACE MODIFICATION OF PROPYLENE-BASED POLYMERS BY SILICON AND TIN-CONTAINING COMPOUNDS

Plasma surface modifications of homo-, co-, and terpolymers of propyle ne films in the presence of selected organosilicon and organotin compo unds were investigated. For this, organosilan(stannan)e type compounds (such as vinyltriethoxysilane, 3-aminopropyltriethoxysilane, and tetr aethylstannane) as well as organosiloxan(stannoxan)e type compounds (s uch as hexamethyldisiloxane and hexabutyldistannoxane) were exployed i n plasma. Plasma surface modification of polyolefin films with organos ilicon plasma has led to increase of the hydrophobicity, while the pre sence of organotin compounds in plasma produced less hydrophobic surfa ces. Reaction of plasma-activated polyolefin films further with vinylt riethoxysilane-maleic anhydride oligomer also led to an increase in th e hydrophobicity of polypropylene surfaces. It is observed that the de grees of swelling of (virgin, plasma-treated, and plasma-modified) pol ypropylene films in cyclohexanone strongly depend on the nature of the organoelement compounds used, organosilicon plasma causing lower degr ees of swelling. The changes of surface properties observed are explai ned by different surface structures produced in plasma: in the case of organosilicon compounds, it is believed that poly(organosiloxane) and for organotin compounds poly(organotincarboxylate) fragments are form ed primarily. (C) 1995 John Wiley & Sons, Inc.