Bis(vinylbenzyl)ether and Bis(vinylbenzyl)thioether: Synthesis, Cure Studies and Evaluation of Carbon Fiber Composites.

摘要

Bis(vinylbenzyl)ether (BVE) and bis(vinylbenzyl)thioether (BVT) have been synthesized from vinylbenzyl chloride in yields greater than 90%. The onset/peak temperatures for thermal cure observed by first-run DSC scans were 80 deg C/11O deg C and 120 deg C/190 deg C, respectively, for BVE and BVT with no Tg in the second run. FT-IR and solid state NMR data indicated that cure occurred mainly through vinyl addition polymerization with high conversions. Composites formed from these resins had flexural modulus values at room temperature comparable to, or better than, traditional epoxy resins. More importantly, however, the BVE and BVT samples maintained much higher moduli than epoxy samples at temperatures above 200 deg C and up to 300 deg C. In addition, thermal cycling to 250 deg C caused ca 50% loss in epoxy composite properties, while BVE and BVT composites maintained their ambient temperature properties. Thermal decomposition of BVT in air occurred at a higher temperatures than BVE, but once degradation began, it was much faster for BVT than BVE as confirmed by DMA and TGA.