PLASMA POLYMERIZATION OF SOME SILICON-CONTAINING AND TIN-CONTAINING MONOMERS

Plasma polymerization of several selected saturated and unsaturated si licon- and tin-containing monomers, such as vinyltriethoxysilane (VTES ), 3-aminopropyltriethoxysilane (APTS), hexamethyldisiloxane (HMDS), h exabutyldistannoxane (HBDS) and tetraethylstannane (TES), were examine d in terms of the following selected plasma operational parameters: di scharge time (t), flow rate of monomer (F) and power input (W). For th e initial deposition rates (DR), the following empirical equation was proposed: DR = k t(a) F-b W-c, from which the experimental values of t he kinetic power factors (a,b,c and k) were calculated. The value of k calculated for VTES was the highest, indicating the high activity of the monomer in plasma in contrast to HBDS, which was about two orders of magnitude smaller. A modified Arrhenius equation was employed in th e form of yield of deposition (DR/F) versus the specific energy (W/F), which showed that silicon-containing monomers are more active than th eir organotin analogues in the chosen plasma conditions. Plasma polyme rs of HMDS, TES and HBDS prepared at low conversions were highly cross linked and their structures were similar to those of crosslinked poly( dialkylsiloxane) or poly(organostannoxane) while those of VTES and APT S were primarily linear.