Synthesis, Cure Kinetics, and Physical Properties of a New Tricyanate Ester with Enhanced Molecular Flexibility

摘要

1,2,3-Tris(4- cyanatophenyl)propane, a new tricyanate ester monomer analogous to cyanated novolac or 'phenolic triazine (PT) resin' that features more flexible chemical linkages at the central branch point, was synthesized in nine steps with an overall yield of 26%. The highly purified monomer exhibited an activation energy of 110 kJ/mol for auto-catalytic cure at temperatures of 210 deg C to 290 deg C, modestly lower than the comparably measured activation energy of a commercial cyanated novolac. The overall extent of cure achievable at these temperatures was also higher for the new monomer. Many physical properties of the cured monomer, including density, thermochemical stability, moisture uptake, and the impact of hydrolytic degradation on glass transition temperature were similar to those of commercial tricyanates, with a dry glass transition temperature at full conversion of at least 340 deg C.