环氧树脂由于其优异的性能被广泛应用于涂料、胶粘剂、电子封装材料等领域,但随着科技的发展,许多高端领域对环氧树脂的耐高温性能提出了更高的要求。首先以甲醇改性硼酚醛树脂,利用甲醇的阻聚作用延缓硼酚醛树脂的交联反应程度,以游离苯酚和凝胶时间为指标设计了正交试验,确定了最佳的改性工艺,制备出了热分解温度465℃,800℃残炭率71.2%的甲醇改性硼酚醛树脂。在此基础上,采用一步法制备了硼酚醛环氧树脂,以甲基纳迪克酸酐为固化剂,研究了不同改性树脂固化物的力学性能和热稳定性。结果表明:随着硼含量的增加,树脂固化物的拉伸强度和断裂伸长率先上升后下降,硼含量为n(硼酸)∶n(苯酚)=0.15∶1的硼酚醛环氧树脂综合性能最优。

Epoxy resin (EP) is widely used in coatings,adhesives,electronic packaging materials and other fields because of its excellent properties.However,with the development of science and technology,many high-end fields put forward higher requirements for the high temperature resistance of EP.Methanol modified boron phenolic resin was used to retard the degree of crosslinking reaction of boron phenolic resin by the inhibition of methanol.The orthogonal experiment was designed based on the free phenol and gelation time.The best modification process was determined,and the methanol modified boron phenolic resin with the thermal decomposition temperature of 465 C and the carbon residue rate of 71.2% at 800 ℃ was prepared.On this basis,boron phenolic EP was prepared by one-step method.Using methylnadic anhydride as the curing agent,the mechanical properties and thermal stability of cured products of different modified resins were studied.The results showed that with the increase of boron content,the tensile strength and fracture elongation of cured products increased first and then decreased.The comprehensive properties of boron phenolic EP with boron content of n(boric acid)∶n(phenol)=0.15∶1 was the best.