单油酸甘油酯琥珀酸单酯羧酸钠盐表面活性剂的合成及性能

Synthesis and Properties of Sodium Carboxylate of Glyceryl Monooleate Succinic Acid Monoester

采用单油酸甘油酯和马来酸酐为原料,以丙酸钠为催化剂,经酯化、碳酸氢钠溶液中和,合成了单油酸甘油酯琥珀酸单酯羧酸钠盐阴离子表面活性剂。通过单因素实验确定了适宜的酯化反应工艺条件:马来酸酐与单油酸甘油酯摩尔比为2∶1;反应时间为1h;反应温度为90℃;催化剂用量10%(相对于单油酸甘油酯的摩尔分数)。单油酸甘油酯琥珀酸单酯羧酸钠盐的表面活性剂性能测试结果表明:该表面活性剂具有优良的性能,25℃时临界胶束浓度ccmc为1.37×10-4mol/L,对应的表面张力γcmc为33.9mN/m,饱和吸附量Γmax为2.52×10^(-10) mol/cm^2,分子最小吸附面积Amin为0.66nm^2,降低表面张力效率因子p(c20)为4.41,泡沫体积为300mL,泡沫稳定性为96.7%,乳化分水时间为144.5s.随着温度升高,ccmc,γcmc和Γmax均减小,Amin和pC20增大,发泡能力增强。

Sodium carboxylate of glyceryl monooleate succinic acid monoester was synthesized by esterification of glyceryl monooleate with maleic anhydride and subsequent neutralization with sodium bicarbonate solution.The esterification reaction parameters with sodium propionate catalyst were optimized in terms of the acid value of the prepared product via single factor variable experiment method.The optimum operating conditions were as follows:maleic anhydride/glyceryl monooleate molar ratio 2∶1,reaction time 1 h,reaction temperature 90℃,and catalyst loading 10%(with respect to glyceryl monooleate).The synthesized surfactant shows good surface active properties:at 25℃,its critical micelle concentration c cmc is 1.37×10^-4 mol/L and the corresponding surface tension(γcmc)is 33.9 mN/m;the saturated adsorption(Γmax)is 2.52×10-10 mol/cm 2,average areas on the saturated adsorption layer(A min)is 0.66 nm 2,efficiency factor for reducing surface tension(p(c 20))is 4.41,its foaming volume is 300 mL and the foam stability is 96.7%;stable time of emulsified liquid could reach 144.5 s.With increasing temperature,c cmc,γcmc andΓmax show the downward tendency,A min and p(c 20)show the tendency of increase,the foaming property is enhanced.