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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 interaction between dodecyl betaine (C12BE) and polyvinylpyrrolidone (PVP) was investigated by surface tension measurement and 13CNMR, ESR spectroscopy. The measurement of surface tension showed that there was a clear interaction between C12BE and PVP and the formation of C12BE / PVP complex under the condition of pH = 6.5 and NaCI. The β-lgc curve of C12BE-PVP mixed solution showed two turning points , The C12BE concentration c1 (C12BE-PVP start associating) at the first turning point is lower than that of C12BE; while at the second turning point, the C12BE concentration c2 (C12BE-PVP association is more than saturated) is greater than the cmc value. (C2 ─ c1) and PVP concentration showed a linear relationship. PVP decreased the standard free energy of C12BE micellization (△ G0) with increasing PVP concentration. The results of 13CNMR show that the methylene groups on the α-CH, β-CH2 and the N on the pyrrole ring of PVP are adsorbed on the hydrocarbon chain of the C12BE micelles, blocking the contact between the C12BE micelles and water . The ESR spectra showed that the viscosity of PVP-C12BE aggregates “interface ” was higher than that of C12BE micelles “interface ”.