非离子活性剂乳液稳定性HLB规则研究

Studies on the HLB rule for non-ionic surfactant

研究了 TX系列乳化剂白油乳液体系稳定特性随 HL B值变化规律 ,测定了活性剂界面吸附层数 ,通过建立非离子表面活性剂界面吸附拔河模型 ,分析了界面活性剂吸附层的结构和组成 (HLB值 )与乳液稳定性之间的关系 ,从而说明了 HL B规则的内在作用机制 .实验还发现随着活性剂用量的增加 ,乳液粒径变小 ,体系的最佳 HL B值升高 ,并根据界面吸附拔河模型对此现象给予了解释 .

Liquid paraffin was emulsified by TX and the stability of corresponding emulsion was measured, A relationship between the stability character with HLB value was found; A method was given to determine the interfacial adsorption quantity of surfactant for the above experiment system; it is interesting to find that when dosage of surfactant increase, the optimum HLB value of the emulsion also increase; A physical model is given to describe the adsorption state of surfactant at the oil-water interface and is used to explain the emulsion stability changing with the HLB value of emulsifier used quite well. According to the model the key factor to get a stable emulsion for the system studied is the appropriate position of surfactant layer at the interface which is determined by the ratio of hydrophilic and hydrophobic surfactant adsorbed. A explanation was proposed for the phenomena that the smaller the droplet, the larger the optimum HLB value it needs.