SiO_2负载磷钨酸催化合成1,4-丁二醇双琥珀酸十八醇双酯磺酸钠

采用1,4-丁二醇、马来酸酐、十八醇为主要原料,合成出一种双子表面活性剂1,4-丁二醇双琥珀酸十八醇双酯磺酸钠。此化合物的合成由两步酯化以及一步磺化反应组成,双酯化反应采用SiO2负载磷钨酸(PW12/SiO2)为催化剂。通过正交实验确定了1,4-丁二醇双马来酸十八醇双酯合成的优化反应条件为:n(1,4-丁二醇双马来酸单酯):n(十八醇)=1.00:2.20,催化剂用量1.5%,反应温度150℃,反应8h,酯化率达到97.2%,产率为84.9%。磺化反应的条件为:n(1,4-丁二醇双马来酸双酯):n(NaHSO3)=1.00:3.00;反应4h;反应温度90℃;催化剂(CTAB)用量1.5%,磺化率达到92.7%,产率为74.9%。在25℃水溶液中测得该表面活性剂的表面张力γcmc为41.9mN/m,CMC为7.2×10-5mol/L。表明该表面活性剂具有很低的临界胶束浓度。

Synthesis of sodium 1,4-butanediol bisulfosuccinate diester catalyzed with PW_(12)/SiO_2

Sodium 1,4-butanediol bisulfosuccinate diester was synthesized from 1,4-butanediod,maleic anhydride and 1-octadecanol.The diesterfication reaction was catalyzed with phosphotungsfic acid supported on silica (PW_(12)/SiO_2).The optimized conditions for the esterification were determined with orthogonal experiments as: molar ratio of 1,4-butanediol bismaleic acid monoester to 1-octadecanol was 1.00 : 2.20,amount of catalyst was co=1.5%,reaction temperatttre was 150℃,reaction time was 8h,the esterification rate could reach to 97.2 % and the yield was up to 84.9%.The sulfonation reaction was carded out with the molar ratio of 1,4-butanediol bismaleic acid diester to NaHSO_3 of 1.00 : 3.00 and1.5% catalyst (cetyltrimethylammonium bromide) at 90℃ for 4h,the sulphonation rate could reach to 92.7 % and the yield was up to 74.9%.The obtained sodium 1,4-butanediol bisulfosuccinate diester has a surface tension γ_(cmc) of 41.9mN/m,a CMC of 7.2×10~(-5) mol/L in aqueous solution at 25 ℃,indicating that the surfactant has a low CMC.