Accession Number:

ADA281414

Title:

Well-Defined Polyphosphazenes by Anionic Polymerization of Phosphoranimines

Descriptive Note:

Final rept. 1 Jun 1991-31 May 1994

Corporate Author:

CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF CHEMISTRY

Personal Author(s):

• Matyjaszewski, Krzysztof

Report Date:

1994-06-20

Pagination or Media Count:

4.0

Abstract:

Polyphosphazenes form an important class of polymers with unique properties which include a combination of high temperature stability, low temperature flexibility, low surface energy, biofriendliness, inflammability, etc. The classic synthetic approach provides very high molecular weight polymers with broad polydispersities and with no control of end groups in low yields and under extreme conditions a few days at temperatures above 200 deg C in a highly corrosive medium. The purpose of the project investigated in our laboratories was to develop alternative routes to polyphosphazenes. New synthesis should provide well defined polymers in higher yields and under milder conditions. Especially important is the control of structural features of polyphosphazenes including control of molecular weights, polydispersities, tacticities and terminal functionalities. We focused our research on catalyzed polymerization of phosphoranimines and synthesis of polydiarylphosphazenes via silyl azide intermediates.

Descriptors:

• *POLYMERIZATION
• *ANIONS
• *PHOSPHAZENE
• LOW TEMPERATURE
• STABILITY
• MOLECULAR WEIGHT
• SURFACES
• CATALYSIS
• FLAMMABILITY
• FLEXIBLE MATERIALS
• PHOSPHORUS
• ARYL RADICALS
• ENERGY
• SYNTHESIS
• HIGH TEMPERATURE

Subject Categories:

• Inorganic Chemistry
• Organic Chemistry
• Physical Chemistry
• Polymer Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE