芳香酮异构化反应影响聚乙烯电击穿强度的理论研究

The mechanism study on effect of aromatic ketones isomerization on the electric breakdown strength of polyethylene

对芳香酮在基态和三重态异构化反应机理进行了理论研究,提出芳香酮的异构化反应是影响聚乙烯电击穿强度的重要因素.通过采用密度泛函理论,计算了芳香酮在基态和三重态异构化反应的稳定点几何构型,完成了简谐振动频率分析,并利用内禀反应坐标理论计算了反应的最小能量路径.研究数据显示,芳香酮在基态和三重态酮式与醇式互换异构反应的能垒均低于聚乙烯碳碳键平均键能.

In this paper, theoretical investigations are completed on mechanism of aromatic ketones isomerization reaction in singlet state and triplet state, respectively. It is proposed that aromatic ketones isomerization reaction is an important factor for influencing the electric breakdown strength of polyethylene. In this paper, density functional theory is employed to calculate the geometries of the stable points in the reaction of ketones isomerization reaction in singlet state and triplet state,and the harmonic vibration frequencies analysis is completed. The intrinsic reaction coordinate （IRC） theory is used to calculate the minimum energy path （MEP）. The research data show that, the energy barriers of aromatic ketones keto-enol form tautomerism reaction in singlet state and triplet state are both lower than the average bond energy of polyethylene carbon-carbon bond.