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非离子型表面活性剂TX 100和TX305,以及阳离子型表面活性剂溴化烷基三甲铵、氯化烷基吡啶和溴化烷基吡啶的水溶液在石英片上的接触角θ~0(石英/水/环己烷悬滴)和θ~n(石英/水/空气悬泡)随浓度的增加皆是先升后降;但θ~w(石英/水滴/环己烷)则随浓度单调增大,最后趋于一极限值。这些结果可以表面活性剂在石英/水界面形成双层吸附和在石英/环己烷界面形成单层吸附的模型来解释。阴离子型表面活性剂烷基硫酸钠在石英上不吸附,故对接触角无影响。但在TX100溶液中加入烷基硫酸钠时,θ~0和θ~w皆随TX100的浓度单调上升;加入的量大时,θ~0、θ~w和θ~a皆近于纯水的θ。这些现象与溶液中形成混合胶团导致TX100的吸附减少有关。
Non-ionic surfactants TX 100 and TX305, as well as the contact angle θ ~ 0 (Quartz / water) of the cationic surfactant alkyltrimethylammonium bromide, alkylpyridinium chloride and alkylpyridinium bromide on quartz wafers / Cyclohexane drop) and θ ~ n (quartz / water / air bubble) increase first and then decrease with increasing concentration, but θ ~ w (quartz / water drop / cyclohexane) , Finally tends to a limit. These results can be explained by the fact that the surfactant forms a bi-layer adsorption at the quartz / water interface and a monolayer adsorption at the quartz / cyclohexane interface. Anionic surfactant sodium alkyl sulfate is not adsorbed on the quartz, it has no effect on the contact angle. However, when sodium alkyl sulfate was added to TX100 solution, θ ~ 0 and θ ~ w all monotonically increased with the concentration of TX100. When the amount of addition was large, θ ~ 0, θ ~ w and θ ~ a were all close to that of pure water θ. These phenomena are associated with the formation of mixed micelles in solution leading to reduced TX100 adsorption.