新型三联季铵盐表面活性剂的合成

Study of New Cationic Trimeric Quaternary Ammonium Salts Surfactant

合成一种三聚阳离子表面活性剂——三(2-氯化十二烷基二甲铵基乙基)胺(TCDAEA)。以三乙醇胺、氯化亚砜为原料,经分子内亲核取代合成(中间体三(2-氯乙基)胺(TCEA);再以(2-TCEA)与N,N-二甲基十二烷基叔胺(12DMA)经季铵化反应合成TCDAEA。实验考察了催化剂质量分数、反应温度、反应时间、溶剂质量分数、(12DMA)与(TCEA)物质的量比等因素对产品产率的影响。结果表明:当氢氧化钾质量分数为0.3%、n12DMA:nTCEA=3.9、溶剂质量分数为20%、反应温度为80℃、反应时间为6h时,产品收率可达96.6%。在25℃、临界胶束浓度为4.2×10-4mol/L时,产品溶液的表面张力降低至25.2mN/m。并用FT-IR方法对中间体(TCEA)和产物TCDAEA进行了结构表征。

A kind of trimeric cationic surfactant-tris（2-chlorododecyl dimethylammoniumethyl）amine（TCDAEA）is synthesized.The tris（2-chloroethyl）amine（TCEA）by intramolecular nucleophilic substitution reactions using triethanolamine and thionyl chloride as materials is firstly prepared.The end products TCDAEA was prepared by quaternization reaction using TCEA and N,N-dimethyl-dodecylamine（12DMA）as materials.Maily studied the effects of mass fraction of catalyst,reaction temperature,reaction time,solvent mass fraction and the molar ratio of 12DMA to TCEA on the yield of product.And used FT-IR method identified the structures of TCEA and TCDAEA.The results show that the intermediate and aim product have been prepared,and the yield of product is 96.6%,when the mass fraction of catalyst is 0.3%,the molar ratio of 12DMA to TCEA is 3.9,solvent mass fraction is 20%,the reaction temperature is 80℃ and the reaction time is 6 h.The surfacial tension of the product solution can reduce to 25.2 mN/m at 25℃ with the critical micelle concentration is 4.2×10^-4 mol/L.