一种季铵盐型低聚表面活性剂的合成及性能

Synthesis and properties of a quaternary ammonium oligomeric surfactant

以季戊四醇为核、通过与分子结构中带有酯基的氯乙酸进行酯化反应,再与N,N-十二烷基二甲基叔胺发生季铵化反应,合成了一种季铵盐型低聚表面活性剂(QTC_(12)·Cl),并通过FTIR、^(1)HNMR等进行表征.通过铂金板法、电导率法和荧光探针法考察了产物的表面性能,结果表明,T=298.15K采用铂金板法测定的产物临界胶束浓度(cmc)为0.46mmol/L、表面张力值(γ_(cmc))为31.15mN/m,与电导率法和荧光探针法测定结果基本一致.采用振荡法和分水时间法测定了产物的泡沫性能和乳化性能,表明产物具有良好的泡沫性能和乳化性能.通过失重法测定该产物在c(盐酸)=1mol/L溶液中的缓蚀性能,c(QTG_(2)·Cl)=7×10^(-4)mol/L时对N80钢的缓蚀率为85.85%,可用作酸洗工作液的金属缓蚀剂.

A quaternary-ammonium-salt tetrameric surfactant(QTC_(12)·Cl)was synthesized by using pentaerythritol as a core and esterification with chloroacetic acid containing two functional groups,and then by quaternisation with N,N-dimethyldodecylamine.The molecular structure and purity of the product were characterized by infrared spectroscopy(FTIR),nuclear magnetic resonance(^(1)H NMR),and elemental analysis.The surface properties of QTC_(12)·Cl were determined by the platinum plate,electrical conductivity and fluorescence probe methods.The results obtained by the platinum plate method show that the critical micelle concentration(cmc)and surface tension(γ_(cmc))are 0.46 mmol/L and 31.15 mN/m at 298.15 K,which are consistent with those obtained by the electrical conductivity and fluorescence probe method.The foam performance and emulsification ability were measured by the oscillation and water splitting time methods,and the results show that these two properties were superior to those of the traditional single chain surfactant dodecyltrimet hylam monium bromide.The corrosion inhibition of QTC_(12)·Cl on N80 steel was measured by the loss-in-weight method in HCl solution of 1 mol/L,and its inhibition efficiency is 85.85%at a concentration of 7×10^(-4)mol/L and the QTC_(12)·Cl may act as a pickling inhibitor.