Synthesis and study of properties of linear permethylpoly(silane-siloxanes)

Heterofunctional polycondensation of ,-dichloropermethyloligosilanes Cl(Me₂Si)_mCl (m = 2—6) with 1,5-dihydroxyhexamethyltrisiloxane was used to synthesize linear permethylpoly(silane-siloxanes) with the regular structure —[(SiMe₂)_mO(SiMe₂O)₃]_n—, which are soluble, unlike polydimethylsilane, in common organic solvents. The use of Py instead of Et₃N as an acceptor of HNl results in an increase in the yield, molecular weight, and characteristic viscosity of the copolymers. The molecular weight and viscosity characteristics, oxidative and thermal stabilities, and spectral properties of the synthesized copolymers were studied. The dependence of the oxidative and thermal stabilities of the synthesized copolymers on the number of the SiMe₂ units in the oligosilane fragment of the main chain was established.