以氢氧根离子催化马来酰亚胺聚合反应为例,通过理论计算探讨了在DMF溶剂(ε=36.7)中阴离子聚合链引发阶段的微观机理,在DFT(B3LYP/6—311G^*)水平搜索得到反应路径,相同水平上对反应物中间体、过渡态和产物进行几何优化和振动分析,并经过IRC验证.发现在反应过程中氢氧根先进攻酰亚胺的碳,经过一过渡态最终生成氢氧根连接在碳碳双键上的阴离子,证明反应机理为阴离子聚合.由于活化能较小,所以聚合反应在较温和的条件下即可进行.
Taking polymerization of maleimide catalyzed by hydroxyl for example, the mechanism of initiated reaction of anion polymerization in DMF has been studied. The reaction path was investigated at the B3LYP/6-311G^* level using DFT method, the geometry Of reactant, product, intermediate and transition state were optimized and frequency analysis were got at the same level. Intrinsic reaction coordinate(IRC) calculation was also performed for getting the further credible results. During the reaction, the hydroxyl firstly attacked the carbon atom of imide and finally formed an anion with hydroxyl linked to C=C by a transition state. The calculation results reveal that the initiated reaction belongs to anion polymerization. For the energy barrier is not light, the polymerition reaction can be conducted in a gentle condition.