低分子量聚苯醚改性氰酸酯树脂的研究

Study on Low Molecular Weight Polyphenylene Oxide Modified Cyanate Ester Resin

采用低分子量聚苯醚(SA90)对氰酸酯(CE)进行改性,并在混合催化剂二月桂酸二丁基锡(DBTDL)和2-乙基-4-甲基咪唑(2E4MI)的作用下,制备了一种改性氰酸酯树脂。研究了SA90含量对改性氰酸酯树脂凝胶化时间、变温拉伸剪切强度、平面应变断裂韧性、介电性能和吸水率的影响。结果表明:随着SA90含量的增加,改性氰酸酯树脂的凝胶化时间逐渐缩短,活化能均在50~70 k J/mol,反应活性较高;当SA90的质量分数为20%时,改性氰酸酯树脂的整体拉伸剪切强度最大;断裂韧性随着SA90含量的增加先增大后减小,当SA90的质量分数为20%时,改性氰酸酯树脂的断裂韧性最佳;适量添加SA90能改善氰酸酯的介电性能以及吸水率。

A low molecular weight polyphenylene oxide(SA90)modified cyanate ester resin was prepared under the action of mixed catalyst of dibutyl tin dilaurate(DBTDL)and 2-ethyl-4-methylimidazole(2E4MI).The effects of SA90 content on the gelation time,variable temperature tensile shear strength,plane strain fracture toughness,dielectric properties,and water absorption of the modified cyanate ester resin were studied.The results show that with the increase of SA90 content,the gelation time of the modified cyanate ester resin is gradually shortened,the activation energy is 50~70 kJ/mol,and the reaction activity is high.When the mass fraction of SA90 is 20%,the modified cyanate ester resin has the largest tensile shear strength.With the increase of SA90 content,the fracture toughness of the modified cyanate ester resin increases at first and then decreases,and when the mass fraction of SA90 is 20%,its fracture toughness is the best.The dielectric properties and water absorption of cyanate ester can be improved by adding proper amount of SA90.