全氟聚乙醚表面活性剂的结构和亲水性质的量子化学研究

STUDY ON STRUCTURE AND HYDROPHILICITY OF PERFLUOROPOLYETHER SURFACTANTS WITH QUANTUM CHEMISTRY

采用量子化学从头算方法研究了全氟聚乙醚羧酸及其负离子的平衡几何构型以及负离子的二水合物和四水合物的氢键作用能 ,探讨了羧酸根—COO-的亲水性质。计算发现 ,氟原子均带有负电荷 ,并包围C—C—O链形成带有负电荷的氟醚链 ;且—COO-是一个很强的亲水基 ,能与 2个或 4个水分子生成很强的氢键 ,水合作用能分别为 - 188.2 42kJ/mol和 - 2 2 6 311kJ/mol。

The equilibrium geometries and interactions of hydrogen bond between perfluoropolyethter surfactants and hydrations of two water and four water moleculars are studied by ab initio GAUSSIAN\|94 program. The hydrophilicity of the group —COO - is discussed. It is found that fluorine atom is of negative charge and forms of C—C—O chain with negative charge around C—C—O chain. Interaction energies of hydrogen bond are -188.242 kJ/mol and -226.311 kJ/mol respectively for hydrogen bonds with two water and four water moleculars.