Effect of Catalyst Dosage on Curing and Properties of Cyanate Ester ResinModified by Polyphenylene Ether

The low relative molecular mass polyphenylene ether containing dihydroxyl end group and bisphenol A cyanate ester modified resin with mass ratio of 1:1 were heat cured with cobalt acetylacetonate as catalyst. The effect of catalyst content (0-0.05wt%) on the curing and properties of the modified resin was studied. The results show that the gelation time of the modified resin decreased with increasing catalyst content or temperature, and when the temperature was higher than 180 ℃, the gelation time changed little with temperature. The curing reaction temperature decreased with increasing catalyst content. The higher the catalyst content, the higher the initial energy storage modulus, the crosslinking density and the glass transition temperature of the modified resin. The dielectric constant and dielectric loss of the modified resin decreased first and then increased, and the water absorption decreased with increasing catalyst content. When the content of catalyst was 0.03wt%, the properties of the modified resin were the best with curing reaction temperature of 160 ℃, glass transition temperature of 210 ℃, water absorption of 0.48%, dielectric constant of 3.51, and dielectric loss of 5.20×10^-3.