Heterofunctional Condensation of α,ω - Bis (Aminodimethylsilil) Tetramethyl - Cyclodisilazanes With Dichloranhydride Tereftalic Acids and α,ω - Bis (β - Carboxyethyl) Dimethylsiloxanes

Abstract

With a view to synthesizing heat-resistant polymers, we performed the heterofunctional condensation (HFC) of α,ω-bis (aminodimethylsilil) tetramethyl- cyclodisilazanes with terephthaloyl chloride. The synthesized polymers are elastic products in light color. Their elasticity increases with an increase in cyclodisilazane fragments in the polymer chain. At temperatures of 360 to 380 0 C, there starts slow polymer degradation, while fast degradation occurs at a temperature of 400 to 450 0 C. We also performed the HFC of α,ω-bis (aminodimethylsilil) tetramethyl- cyclodisilazanes with α,ω-bis ( -carboxyethyl) dimethylhexanes. The synthesized products are caoutchouc-like products, as they contain pliant siloxane and cyclodisiloxane fragments. They have quite high thermal stability. The stability is impacted on by an increase in the dimethylsiloxane block in the copolymer chain. Polymers are resistant at temperatures of 510 to 550 0 C. At these temperatures, there starts their slow degradation. The thermal stability of polymers is not impacted on by an increase in the share of silazane cycles in the chain.