Guerbet十四醇聚氧乙烯醚硫酸钠的合成与表面活性

以Guerbet十四醇 (C14 GA)为中间体 ,经Williamson反应合成Guerbet十四醇聚氧乙烯醚醇〔C14 GA(EO) nH ,n =1,2 ,4〕 ,再经氯磺酸酯化及NaOH中和 ,得到阴离子表面活性剂Guerbet十四醇聚氧乙烯醚硫酸钠〔C14 GA(EO) nS ,n =1,2 ,4〕。用IR、NMR和元素分析测定了所合成的表面活性剂的结构 ,并利用表面张力法测定了这些表面活性剂水溶液的表面活性。实验结果表明 :所合成的表面活性剂的结构分别为C14 GAEOS (A) ,C14 GA(EO) 2 S(B)和C14 GA(EO) 4 S(C) ;这些表面活性剂其临界胶束浓度CMC(mmol/L) ,在CMC时的表面张力γCMC(mN/m)和Krafft点 (℃ )分别为A :2 5 8mmol/L ,2 7 6mN/m ,5 9℃ ;B :0 80mmol/L ,2 6 4mN/m ,2℃和C :0 12mmol/L ,2 5 3mN/m ,0℃。均比常用的直链阴离子表面活性剂C12 H2 5SO4Na(8.6mmol/L ,4 1 2mN/m ,16℃ )有更低的CMC ,γCMC和Krafft点 ;聚氧乙烯基的引入 ,对降低CMC ,γCMC和Krafft点的效果随氧乙烯基团数目的增多 (由 1增至 4 )而加大。讨论了表面活性剂的结构和表面活性的关系

Synthesis and Surface Activity of Sodium Guerbet Tetradecyl Polyoxyethylene Ether Sulfates

Using Guerbet tetradecyl alcohol (synthesized by Guerbet reaction using n heptanol as raw material) as intermediate,Guerbet tetradecyl polyoxyethylene ether sulfates[C 14 GA(EO) n S, n =1,2,4] were obtained through following steps:synthesizing Guerbet tetradecyl ether polyethylene alcohols[C 14 GA(EO) n H, n =1,2,4] by Williamson reaction,then esterifying with chlorosulfonic acid and neutralizing with sodium hydroxide.The structures of these surfactants were identified by IR,NMR and elementary analysis. The surface activities of water solutions of these surfactants were determined by surface tension method.The experimental results show that the synthesized surfactants conform to the following structures:C 14 GAEOS(A),C 14 GA(EO) 2S(B) and C 14 GA(EO) 4S(C);their critical micelle concentration CMC (mmol/L),surface tension at CMC γ CMC (mN/m) and Krafft point (℃) [being respectively A(2 58 mmol/L,27 6 mN/m,5 9 ℃),B(0 80 mmol/L,26 41 mN/m,2 ℃) and C(0.12 mmol/L,25 34 mN/m,<0 ℃)] are lower than that of common surfactant C 12 H 25 SO 4Na (8 6 mmol/L,41 2 mN/m,16 ℃);moreover,the effects of introducing oxyethylene group on reduction of the CMC, γ CMC and Krafft point enhance with increase of oxyethylene group number ( n =1-4).The relationship between structure and surface activity of surfactant was discussed.