Heat Resistant Polymers Containing the Low Molecular Weight Closo-Carboranes. II. Thermal Behavior of Poly SiB-1Elastomers from C2B5H7.

摘要

Unmodified 5-SiB-1polymers have been found to be at least equivalent to their 10-SiB-1counter-parts with respect to thermal stability. The 5-SiB-1polymers,moreover,are substantially more amenable to conversion into elastomers. The introduction of 15to 20mole per cent of m-C2B10into the 5-SiB-1backbone results in elastomers whose thermal stability,although less than that of the parent homopolymer is,nevertheless,substantially in excess of the published values for other carboranesiloxane polymers. The crystallization of the 5-SiB-1copolymer containing 15mole per cent C2B10was inhibited by irradiation with 50 megarads of 3mev betas. The 5-SiB-1copolymer containing 20mole per cent C2B10on the other hand,remained a rubber at room temperature. (Author)