Synthesis and Thermal Properties of Aryl and Aryloxyethynyl Monomers for Thermoset Resins of Reduced Crosslink Density

摘要

A series of thermoset matrix materials with phenylethynyl and pheno yphenylethynyl end groups were presented to assess the extent of crosslinking in the cured resins by thermo-analytical and thermomechanical methods. These novel materials with varying flexibility and thermal stability of both the end group and backbone were evaluated against a group of materials (AT systems) known to contain a substantial number of primary acetylenic thermal crosslinking sites. The evaluation indicated the increased thermooxidative stability of the secondary acetylenic materials over the AT systems at or below 600 F (312 C). However, above 600 F the reverse observation was true since the phenyl pendant of the secondary termini was thermally decomposed near 400 C (752 F) as measured by MS/TGA under vacuum. Cure exotherms (T poly) for monomers exhibited typical Gaussian behavior with discernable cure onsets and maxima. Thermoset matrix materials, Epoxy resins, Thermooxidatively stable, Crosslinking, (Chemistry), Monomers, Phenylenes, Imides, Thermomechanical properties. (JES)