Cyclic Silicon Organic Copolymers: Synthesis and Investigation. Review

This paper considers the synthesis and investigation of cyclic silicon-organic polymers with mono- and polycyclic fragments in the side chain. For obtaining monocyclic polymers, the hydrosilylation reaction of 1-hydro-3-vinylhexamethylcyclotetrasiloxane was used. The reaction was conducted in a CCl4 solution at 75°C in the presence of Speier’s catalyst (H2PtCl6  6H2O) to produce a viscous-flow at room temperature polymer. The polymers were studied by NMR spectroscopy. Poly(carbosiloxane) with cyclic fragments in the methyl-siloxane backbone was synthesized by the hydride polyaddition of divinylorganocyclosiloxane with dihydrodimethylsiloxane. A semi-quantitative assessment conducted using NMR spectroscopy revealed the ratio of isomeric 1,3- and 1,5-cyclic structures as 1:1. X-ray diffraction studies indicated that copolymers are single-phase amorphous systems. Also, in the review, synthesis and studies of carbosiloxane copolymers containing flexible dimethylsiloxane and decaorganotricyclodecasiloxane fragments in the backbone are discussed. Hydride polyaddition of divinyl-containing compounds was carried out for -dihydridedimethylsiloxanes of various lengths. The synthesized copolymers were characterized by the X-ray diffraction method and TGA.