预聚时间对 CE/EP 树脂体系固化行为的影响

Phenolic epoxy resin was used to modify cyanate ester resin and solve the problem of crystallization and precipitation of CE resin at room temperature by means of pre-polymerization. The pre-polymerization process of modified CE/ EP resin system was traced by gel time, differential scanning calorimetry (DSC), infrared spectroscopy (IR), rheometer and gel permeation chromatography (GPC). The effects of pre-polymerization time on gel time, curing reaction, molecular structure, rheological behavior, relative molecular mass and metallographic structure of composites were investigated, and the pre-polymerization parameters of modified CE resin were obtained. The results show that the curing reaction of phenolic epoxy modified CE/ EP resin system includes one endothermic zone and two exothermic zones, and the products with different chemical structures are formed; the curing degree, viscosity and relative molecular mass of the modified CE/ EP resin system gradually increase with the extension of pre-polymerization time, but gel time obviously decrease; the pre-polymerization time also affect the metallographic structure of carbon fiber composites, and the porosity decrease gradually with the extension of pre-polymerization time. The control methods for viscosity and relative molecular mass of modified CE/ EP resin are obtained. Reducing curing temperature as well as improving wettability and adhesion between CE resin and carbon fiber can provide high-performance resin matrix for preparing high-performance carbon fiber prepreg and engineering application.