Elastomeric and mechanical properties of poly‐m‐carboranylenesiloxanes

Abstract
A new high‐temperature elastomer, SiB‐2, has been investigated by stress relaxation, modulus‐temperature, and volume‐‐temperature techniques. SiB‐2 was found to be more stable than a related elastomer, radiation‐cured silicone rubber, having about twice as long as a chemical relaxation time at 250°C. Possible mechanisms to account for this increased stability are discussed. At low temperatures, Tg for SiB‐2 was estimated at –34°C., which compares well with Ti = −30°C. for this polymer. By comparison, SiB‐3 has Ti = −60°C., while phenyl‐modified SiB‐4 was found to have Ti = −25°C. Tm for SiB‐2 was estimated to be + 56°C.

This publication has 15 references indexed in Scilit: