High-temperature stability of a novel phenylethynyl liquid-crystalline thermoset

✍ Scribed by Arthur J. Gavrin; Christine L. Curts; Elliot P. Douglas

• Book ID: 101275639
• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 138 KB
• Volume: 37
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19991115)37:22<4184::aid-pola18>3.0.co;2-q

✦ Synopsis

We report the synthesis of a new high-temperature liquid-crystalline thermoset based on the phenylethynyl functional group. The monomer was a nematic thermotropic liquid crystal with a melting temperature of 268 °C. The extrapolated onset of the cure exotherm occurred at 313 °C. The cured thermoset retained the nematic liquid-crystalline order of the parent monomer. The monomer and crosslinked resin were characterized by differential scanning calorimetry, optical microscopy, and thermogravimetric analysis. The thermal stability of the crosslinked resin was determined in both air and nitrogen atmospheres at various heating rates. The onset of weight loss in air and nitrogen atmospheres was determined to be 397 and 422 °C, respectively, for a heating rate of 10 °C/min.