离子型表面活性剂对双重乳粒分散性能的影响

为了改善臭氧处理PS单层球与PVA溶液生成的双重乳粒在油相中的分散性,采用了低分子量阴离子型表面活性剂十二烷基硫酸钠(SDS)和十二烷基苯磺酸钠(SDBS)及高分子量混合型表面活性剂十八烷基胺聚氧乙烯醚双季铵盐(PAVDA)来改性该种PS单层球,测试并分析了不同表面活性剂对相应薄膜亲水接触角及其对PVA吸附速率的影响,同时也考察并对比了静电排斥作用和空间位阻作用对双重乳粒分散性的影响。实验结果表明这三种表面活性剂均能不同程度的改善双重乳粒在油相中的分散性。其中,经SDS和SDBS处理后,双重乳粒在油相中固化时会发生絮凝作用而无法以较高成活率制得大尺寸双层球;经PAVDA处理PS单层球后,实现了以较高的成活率制得700~900μm的PS-PVA双层空心微球。同时,也表明在改善PS单层球的分散性方面,空间位阻稳定作用较静电排斥作用更为有效。

Influence of ionic surface active agent on distribution properties of PS-PVA double emulsion

We adopted the anion surface active agents SDS, SDBS and mixed surface active agent polyoxyethylene alkyl vinyl double ammonium (PAVDA) to treat polystyrene (PS) monolayer microspheres and improve the distribution of ozonized PS-PVA double emulsion in the oil. The influences of various surface active agents on the contact angle and different absorption rates of PVA on PS film were tested and analyzed. Moreover, the effects of electrostatic repulsion and special resistance on the distribution of monolayer microspheres were also studied. Experimental results show that all of above-mentioned surface active agents can improve the distribution of PS monolayer microspheres to some extent. As for double emulsion treated by SDS and SDBS, because of the flocculation which happened in the oil phase during curing, it was difficult to form large-size microspheres. Specially, we gained about a half surviving rate of PS-PVA double-layer hollow microspheres (700-900 μm in diameter), when treating them with PAVDA solution. The results also indicate that space hindrance is more effective than electrostatic repulsion to modify the distribution of PS microspheres.