Toughening of cyanate resin with low dielectric constant by glycidyl polyhedral oligomeric silsesquioxane

Abstract

In this article, a high-performance hybrid material was prepared by melt blending from glycidyl polyhedral oligomeric silsesquioxane (G-POSS) and bisphenol-A cyanate ester (CE), using triethylamine as the curing agent. The structure of the hybrid was characterized by Fourier transform infrared spectroscopy and scanning electron microscopy (SEM), and the transparency properties, mechanical properties, dielectric properties, thermal performance, and wet fastness were studied. The results showed that G-POSS was uniformly distributed in the CE matrix and could obviously accelerate the curing reaction of the resin. Large amounts of corrugated and scaled structures were observed on the fractures of G-POSS/CE by the SEM photos. When the G-POSS content increased to 7 phr, the tensile strength (75.45 MPa), elongation at break (3.19%), and impact strength (23.76 kJ m−2) reached maximum values, representing increases of 21.75%, 27.6%, and 157.98% relative to that of pure CE, respectively, which indicated that the addition of G-POSS can significantly improve the toughness of G-POSS/CE composites. When the G-POSS content increased to 4 phr, the dielectric constant decreased from 3.27 to the minimum value of 3.05. The heat resistance and wet fastness of G-POSS/CE hybrid materials decreased with increasing G-POSS content.