Oligo(urethanesiloxane methacrylates) and the related polyurethanes

New polymerizable oligomers oligo(urethanesitoxane methacrylates) capable o f photoinitiated curing with the formation of poly(urethanesiloxane methacr ylates) were synthesized by the polyaddition reaction. The morphology and t hermal, physicochemical, and mechanical characteristics of the above compou nds were studied. It was established that the X-ray measured degree of segr egation in the oligo- and poly(urethanesiloxane methacrylates) significantl y exceeds the corresponding value for oligo- and poly(urethane methacrylate s) containing flexible oligooxypropylene blocks, independent of the flexibl e block length. It was shown that the siloxane-containing polyurethanes sho w a higher thermal stability compared to poly(urethane methacrylates), inde pendent of the flexible block length.