Accession Number:

ADA059057

Title:

The Preparation and Properties of D2-m-Carboranesiloxane Polymers.

Descriptive Note:

Final rept. 1972-1978,

Corporate Author:

UNION CARBIDE CORP TARRYTOWN NY MEDICAL PRODUCTS DIV

Report Date:

1978-07-01

Pagination or Media Count:

129.0

Abstract:

Linear D2-m-carboranesiloxane polymers Mw 150,000-250,000 were prepared from 1,7-bishydroxydimethylsilyl-m-carborane and bisn-phenyl-N,N-tetra-methyleneureidodialkylsilanes as condensation monomers. Improved methods of monomer preparation and purification were developed. The polymers exhibit outstanding high temperature stability and retention of elastomeric behavior. The preferred central silicon substitution pattern is 67 dimethyl-33 methyl-phenyl. Filled and cured vulcanizates gave long-term elastomeric performance from -25 C to or 300 C. The preferred fillers are hydrophobic silicas, the preferred curing agents are peroxides, and the preferred antioxidant is ferric oxide. Radiation resistance, flammability, and solvent resistance were evaluated 3,3,3-trifluoropropyl groups were introduced to enhance the latter. Synthesis of a specifically carboranesilanol-terminated polymer allowed preparation of ultra-high molecular weight polymer M 1 million and alternating block copolymers however, its synthesis proved difficult to reproduce for unidentified reasons. Author

Subject Categories:

  • Polymer Chemistry
  • Elastomers and Rubber

Distribution Statement:

APPROVED FOR PUBLIC RELEASE