十二烷基甜菜碱与聚乙烯吡咯烷酮相互作用的研究  

The Interaction Between Dodecyl Betaine and Polyvinylpyrrolidone

作　　者：郝京诚[1] 梁芳珍[1] 刘树海[1] 任建成[1] 鲁绍芬[1] 李干佐[2] 汪汉卿[3] 

机构地区：[1]山东师范大学表面与界面化学实验室,济南250014 [2]山东大学胶体与界面化学研究所,济南250100 [3]中国科学院兰州化学物理研究所,兰州730000

出　　处：《高等学校化学学报》1998年第1期111-115,共5页Chemical Journal of Chinese Universities

基　　金：国家教育委员会山东大学胶体与界面化学开放实验室资助

摘　　要：通过表面张力测定和13CNMR、ESR波谱研究了十二烷基甜菜碱（C12BE）与聚乙烯吡咯烷酮（PVP）的相互作用．表面张力测定表明，在pH＝6．5及NaCI存在下，C12BE与PVP之间有明显的相互作用，可形成C12BE／PVP复合物，且C12BE－PVP混合溶液的β－lgc曲线出现2个转折点，第一个转折点时C12BE浓度c1（C12BE－PVP开始缔合）低于C12BE的cmc值；而第二个转折点时C12BE浓度c2（C12BE－PVP缔合达饱和）大于cmc值．（c2─c1）与PVP浓度呈线性关系．PVP降低C12BE胶束化标准自由能（△G0）随PVP浓度增加而增大．13CNMR测定表明，PVP骨架上α-CH、β-CH2和吡咯环上与N相连的亚甲基吸附于C12BE胶束表面的碳氢链部位，屏蔽了C12BE胶束表面碳氢链与水的接触．ESR波谱表明，PVP－C12BE聚集体"界面"的粘度高于C12BE胶束"界面"的粘度．The association and standard free energy of formation of the complex between dodecyl betaine(C12BE) and polyvinylpyrrolidone(PVP) in aqueous solution have been investigated by using 13C NMR, ESR and surface tension measurement on the air/water interface.It is found that the basic structure of the complex is a micelle-like aggregate, the C12BE molecules were assembled on the methine(α), methylene(β) carbon in the backbone, and the methylene carbon attached to the nitrogen of PVP molecules, and shielding hydrocarbon groups on the surface of the micelle from contact with water. Our results also confirm that the micellization process in the presence of PVP occurs at a lower concentration than that at the critical micelle concentration. The effectiveness of PVP in lowering the free energy of formation of the surfactant aggregates in aqueous solutions increases with the increasing concentrations of PVP. The interfaclal viscosity of the aggregates of PVP-C12BE is higher than that of C12BE ones.

关 键 词：十二烷基甜菜碱 聚乙烯吡咯烷酮 表面活性剂 

分 类 号：O647.2[理学—物理化学]