一种螺环原碳酸酯膨胀单体的合成及其与环氧树脂热固化

Synthesis of a spiro orthocarbonate expanding monomer and its thermocuring with epoxy resin

经两步法合成了一种螺环原碳酸酯类膨胀单体,该单体在固化剂三氟化硼乙胺催化作用下,能进行阳离子双开环聚合反应,并讨论了该单体聚合反应机理。采用差示扫描量热(DSC)跟踪环氧树脂及其被膨胀单体改性后的固化反应过程,发现纯环氧树脂存在2个固化反应放热峰,而改性树脂仅有一个反应放热峰。结果表明:膨胀单体和环氧树脂进行了开环共聚反应,膨胀单体的加入能提高环氧基团的转化率。

A spiro orthocarbonate expanding monomer was synthesized by two steps. Its cationic double ring-opening polymerization was carried out with (BF_3·C_2H_5NH_2) as catalyst, and then the mechanism of polymerization was put forward. The curing processes of epoxy resin with or without expanding monomer were traced by differential scanning calorimeter (DSC). It was found that DSC curves showed two peaks in the case of pure epoxy resin, but only one peak for the epoxy resin mixing with expanding monomer. As a result, the open-ring copolymerization was undergone between the expanding monomer and epoxy resin, and the addition of the expanding monomer into the epoxy resin enhanced the conversion of epoxy group.