阳离子型三硅氧烷表面活性剂的合成及其界面性能

Synthesis and interfacial properties of cationic trisiloxane surfactant

摘要:

在铂催化下，1,1,1,3,5,5,5-七甲基三硅氧烷（MDHM）和端烯丙基环氧基聚醚（APEE）经硅氢加成反应先制得聚醚环氧基三硅氧烷(PEETS)，再将其与二乙醇胺(DEA)进行开环反应合成出了一种新型阳离子型三硅氧烷表面活性剂(CTSS)。用IR和1H-NMR对CTSS的结构进行了表征，并对CTSS的界面性能进行了测定。结果表明：PEETS和CTSS的收率分别为90.6%（以MDHM和APEE为基准）和91.8%（以PEETS和DEA为基准）。CTSS的黏度约为2 600 mPa•s、折射率为1.4742。在临界胶束浓度为8.7×10-4 mol•L-1 时，CTSS水溶液的表面张力约为25.8 mN•m-1。饱和吸附量、饱和吸附层中每个CTSS分子所占的平均面积和形成胶束的标准自由能分别为4.9×10-6mol•m-2、0.34nm2和-27.4kJ•mol-1。

Abstract:

Abstract: A new kind of cationic trisiloxane surfactant (CTSS) was synthesized by the ring-opening reaction of polyether epoxy group trisiloxane (PEETS) with diethanolamine. PEETS was prepared by hydrosilylation from 1,1,1,3,5,5,5-heptamethyltrisiloxane (MDHM) and allyl polyoxyalkylene glycidol ether (APEE) in the presence of platinum catalyst. The chemical structure of CTSS was characterized by IR and 1H-NMR. The interfacial properties of CTSS were mensurated. Experimental results showed as follows. The yields of PEETS and CTSS are 90.6% (based on MDHM and APEE) and 91.8% (based on PEETS and DEA), respectively. The viscosity and refractive index of CTSS are 2 600 mPa•s and 1.4742, respectively. In the critical micelle concentration of 8.7×10-4 mol•L-1, the surface tension of CTSS aqueous solution reduced to approximately 25.8 mN•m-1. The saturated adsorption, single CTSS average areas on saturated absorption layer and micellization standard free energies are 4.9×10-6 mol•m-2, 0.34 nm2 and -27.4 kJ•mol-1, respectively.