The free radical polymerization of Vinyl Acetate onto silica particles was studied with the goal of elucidating the kinetics of the reaction process. The process consists of three sequential steps: Acid pretreatment of the silica particles, silylation and free radical polymerization. In the pretreatment step, the silica particles are cleaned and converted to hydroxylated state. In the silylation step, the precursor, unsaturated double bonds is introduced onto the silica surface. The free radical polymerization is initiated by an azo-initiator. The polymerization graft yield of polymerization and conversion were determined as a function of reaction temperature, monomer and initiator concentrations. In addition, the morphology of the restulting grafted polymer phase was evaluated by atomic force microscopy. It was demonstrated that reaction conditions have a significant impact on the morphology of the graft polymerized poly(vinyl acetate) surface phase.

1. Renyuan Qian, Jinshu Shen, Nianjiong Bei, Chunli Bai, Chuanfeng Zhu, and xinwen Wang, Morphological observations of single-chain glassy polystyrene by means of tapping mode atomic force microscopy. Macromol. Chem. Phys. 197, 2165-2174 (1996).
2. Cohen, Y., J-D, Jou, W. Yoshida and N. Nei, "Surface Modification of Oxide Surfaces by Graft Polymerization," in "Oxide Surfaces", J. A. Wingrave (Editor), Marcel Dekker, New York, in press.
3. Cohen, Y., W. Yoshida, Jeng-Dung Jou, Hiroyoshi Ohya, Nianjiong Bei "Ceramic-supported Polymer (Csp) Membranes for Pervaporation Separation of Organic/aqueous and Organic/organic Mixtures", International Conference on Membranes (ICOM), June 12-18, 1999, Toronto, Ontario, Canada.