Isotactic polymers of silicon‐containing vinyl monomers

Abstract

Publisher Summary This chapter discusses isotactic polymers of silicon-containing vinyl monomers. The polymerization of silicon-containing vinyl monomers by means of conventional processes yields only low molecular weight polymers. High molecular weight polymers from monomers containing one vinylic unsaturation and one silicon atom have been prepared by using heterogeneous catalysts which act according to a mechanism of coordinated anionic catalysis. Such polymers contain linear, head-to-tail macromolecules having regular structure, and are crystallizable. By polymerization of allyltrimethylsilane in heptane solution at a temperature of 70–80°C in the presence of catalysts prepared by the reaction of triethyl aluminum with titanium tetrachloride, crude polymers having high molecular weight can be obtained with good yields. The crude polymers, obtained from allyltrimethylsilane, have a silicon content of 24–35% and an intrinsic viscosity in tetralin at 135°C of about 0.5.