The Preparation and Properties of D2-Carborane-Siloxanes.
UNION CARBIDE CORP TARRYTOWN N Y CORPORATE RESEARCH LAB
Pagination or Media Count:
UCARSIL, D2-meta-carborane-siloxane polymer, has been developed for ultrahigh temperature elastomer applications. It offers a unique combination of properties unavailable with fluorocarbon, silicone, or polyphosphazine based high performance elastomers. In particular, UCARSIL has superior thermal stability 300 C in air in addition to fire and chemical resistance, and good processing characteristics. An improved synthesis of bis-ureidosilane monomers has been devised which gives 98 purity. A simple and efficient recycling process for recovering m-carborane from unsuitable UCARSIL polymer has been developed. An investigation of the effects of backbone modifications, extending fillers, molecular weight, and peroxide content was carried out during the past year. Performance correlations exist for a large number of variables. This has led to a highly optimized system which allows exploitation of the potential of the D2-polymer in high temperature vulcanized elastomer application. D2-carborane-methyltrifluoropropyl-siloxane vulcanizates and block copolymers of UCARSIL were characterized.
- Polymer Chemistry