Accession Number:

ADA625631

Title:

Thermal Stability of Fluorinated Polydienes Synthesized by Addition of Difluorocarbene

Descriptive Note:

Journal article

Corporate Author:

TENNESSEE UNIV KNOXVILLE DEPT OF CHEMISTRY

Report Date:

2012-01-01

Pagination or Media Count:

11.0

Abstract:

Linear PCHD and polyisoprenes with different microstructures and molecular weights are synthesized and chemically modified to improve their thermal and chemical stability by forming a three-membered ring structure containing two C-F bonds. Pyrolysis of these fluorinated polydienes proceeds through a two-stage decomposition involving chain scission, crosslinking, dehydrogenation, and dehalogenation. The pyrolysis leads to graphite-like residues, whereas their polydiene precursors decompose completely under the same conditions. The fluorination of PCHD enhances its thermal stability. The stronger C-F bond along with high strain of the three-membered ring structure and formation of relatively stable free radicals play an important role in the thermal stability of fluorinated polydienes.

Subject Categories:

  • Organic Chemistry
  • Physical Chemistry
  • Polymer Chemistry
  • Thermodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE