可分解香兰素基非离子表面活性剂的乳化性

The emulsibility of cleavable vanillin-based nonionic surfactants

针对已合成的含缩醛结构的环保型非离子表面活性剂香兰素辛二醇缩醛聚氧乙烯醚(VAEO),研究不同乙氧基链长的VAEO_n(n=6～24)的表面活性及乳化性,并与壬基酚聚氧乙烯醚(NPEO_(10))的表面活性及乳化性作比较。结果表明,随EO聚合度(n)增大,VAEO_n降低表面张力和油/水界面张力的能力下降,对石蜡乳化能力减弱。EO聚合度为6～10的VAEO_n与NPEO_(10)降低表面张力的能力相近,乳化性能也相当。VAEO_n降低油/水界面张力的能力较NPEO_(10)差。采用Material Studio软件模拟分析VAEO_n和NPEO_(10)乳化石蜡的能力,结果表明VAEO_n乙氧基链越长,乳化石蜡重新聚集的速度越快,即乳化性能越差,模拟结果与乳化石蜡分相法的实验结果相吻合。

A series of environment-friendly nonionic surfactants,vanillin 1,2-octanediolacetal polyoxyethylene ethers(VAEO)with acetal structure,have been successfully synthesized previously.The surface activity and emulsibility of VAEOn(n=6-24)were studied,which were also compared with that of nonylphenol polyoxyethylene ether(NPEO10).The results show that,as the polyoxyethylene chain length(n)of VAEOnincreased,the abilities of VAEOn to reduce the surface tension/interfacial tension and to emulsify paraffin are both decreased.As for the VAEOn with low degree of EO polymerization(n=6-10),their surface activity and emulsibility are similar to those of NPEO10.The ability of VAEOn to reduce oil-water interfacial tension is worse than that of NPEO10.The software'Material Studio'is used to simulate VAEOn and NPEO10 in emulsifying paraffin in water,showing that the paraffin aggregated faster for the VAEOn with longer polyoxyethylene chain length,which is consistent with the experimental results by split-phase method.