Accession Number:

ADA235358

Title:

Preparation and Degradation of Polysilylenes

Descriptive Note:

Technical rept. no. 25, May 1990-May 1991

Corporate Author:

CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF CHEMISTRY

Personal Author(s):

• Matyjaszewski, Krzysztof

Report Date:

1991-05-02

Pagination or Media Count:

35.0

Abstract:

Mechanistic aspects of preparation and degradation of polysilylenes polysilanes are discussed. Reductive coupling of disubstituted dichlorosilanes at ambient temperatures in the presence of ultrasound leads to monomodal polymers with relatively narrow molecular weight distributions M sub wM sub n from 1.2 to 1.5 and relatively high molecular weights M sub N from 50,000 to 100,000. Ring-opening polymerization of cyclotetrasilanes initiated with carbanions and silyl anions provides polymers with molecular weights from 10,000 to 100,000 and gives potential possibility of the microstructure control. Synthesis and solid state transitions in random copolysilylenes are discussed. Thermal, mechanical, and chemical degradation of polysilylenes is described.

Descriptors:

• *POLYSILANES
• *BIOSYNTHESIS
• MICROSTRUCTURE
• DEGRADATION
• POLYMERIZATION
• MOLECULAR WEIGHT
• ULTRASONICS
• TRANSITIONS
• DECOMPOSITION
• THERMAL DEGRADATION
• CHEMICAL ATTACK(DEGRADATION)

Subject Categories:

• Inorganic Chemistry
• Polymer Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE