离子型碳氟与碳氢表面活性剂在胶团及吸附层中的分子间相互作用

本工作研究了二元表面活性剂溶液的热力学, 考虑了反离子对表面活性离子在表面相和胶团中的相互作用的影响, 得出计算分子相互作用参数β_m和β_σ的将遍公式(β_m和β_σ分别代表胶团和吸附层中的分子相互作用参数):β_m=ln[((cmc_1)/(cmc_1~0x_(1m)))(c″_1/c′_1)~(K_1)]/x_(2m)~2=ln[((cmc_2)/(cmc_2~0x_(2m)))(c″_2/c′_2)~(K_2)]/x_(1m)~2β_σ=ln[((c_1(π))/(c_1~0(π)x_(1σ)))(c″_1/c′_1)~(K_1)]/x_(2σ)~2=ln[((c_2(π))/(c_2~0(π)x_(2σ)))(c″_2/c′_1)~(K_2)]/x_(1σ)~2作为极限情况, 此式对于非离子型表而活性剂或有过量无机电解质时可简化为:β_m=ln[(cmc_1)/(cmc_1~0x_(1m)]/x_2m~2=ln[(cmc_2)/(cmc_2~0x_(2m)]/x_(1m)~2β_σ=ln[(c_1(π))/(c_1~0(π)x_(1σ)]/x_2σ~2=ln[(c_2(π))/(c_2~0(π)x_(2σ)]/x_(1σ)~2应用公式于各类型碳氟、碳氢表面活性剂二元混合溶液, 包括正离子-负离子、负离子-负离子、负离子-非离子混合体系。自表、界面张力-浓度关系计算各体系的β_m及β_σ。结果表明：(1)碳氟、碳氢正离子-负离子表面活性剂混合体系的β_m及β_σ有很大的负值, 表示有强烈的分子相互作用；(2)碳氟链与碳氢键间存在“互憎性”。这种“互憎性”在负离子-负离子混合体系及非离子-负离子混合体系中皆有明显表现；(3)表面压维持恒定时, 不论表面或溶液内部的表面活性剂的摩尔分数如何变化, β_σ值一般近于常数；(4)表面压越高则分子相互作用越强, 表现为β_σ绝对值变大。

MOLECULAR INTERACTION BETWEEN IONIC FLUOROCARBON AND HYDROCARBON SURFACTANTS IN MICELLES AND ADSORPTION LAYERS

The thermodynamics of the solution of binary mixture of surfactants has been studied.Considering the effect of counterion on the interactions between the surf- ace active ions in the micelle and at the interface,the general equations for calcu- lating the molecular interaction parameters in the micelle (β_m) and at the interface (β_σ) have been obtained: β_m=ln[(cmc_1)/(cmc_1~0x_(1m))(c″_1/c′_1)~(K_1)]/x_(2m)~2=ln[(cmc_2)/(cmc_2~0x_(2m)(c″_2)/(c′_2)~(K_2)]/x_(1m)~2 β_σ=ln[((c_1(π))/(c_1~0(π)x_(1σ)))(c″_1/c′_1)~(K_1)]/x_2σ~2=ln[((c_2(π))/(c_2~0(π)x_(2σ)))(c″_2/c′_1)~(K_2)]/x_(1σ)~2For the nonionic surfactants mixtures or the ionic ones in the presence of excess of inorganic electrolytes, as a limited case, the general equations reduce toβ_m=ln[(cmc_1)/(cmc_1~0x_(1m)]/x_2m~2=ln[(cmc_2)/(cmc_2~0x_(2m)]/x_(1m)~2β_σ=ln[(c_1(π))/(c_1~0(π)x_(1σ)]/x_2σ~2=ln[(c_2(π))/(c_2~0(π)x_(2σ)]/x_(1σ)~2...