Chemical grafting of poly(vinyl acetate) onto montmorillonite 20A nano-particles

This paper is an account of the experiments on grafting poly(vinyl acetate) onto organophilic montmorillonite. Cloisite 20A was reacted with vinyltrichlorosilane to achieve the replacement of the edge hydroxyl groups of the clay by vinyl moiety. Since the reaction liberates HCl, it was performed in the presence of sodium hydrogencarbonate. This prevents the exchang of quaternary alkylammonium cations with H+ ions, and only edge silanol groups of clay react with vinyltrichlorosilane. The product maintained the same basal spacing as the precursor. The radical polymerization of the product with vinyl acetate as a vinyl monomer leads to chemical grafting of poly(vinyl acetate) onto montmorillonite surface. Homopolymer formed during polymerization was Soxhelt extracted from grafted organoclay. Chemical grafting of polymer onto Cloisite 20A was confirmed by IR spectroscopy. The interlayer changes of the clay in the prepared nanocomposite materials and grafted nano-particles were studied by XRD.

کلیدواژه ها:

Grafting ، Poly(vinyl acetate) ، Nanocomposites ، Cloisite 20A ، Organophilic clay