Two kinds of surfactants,sodium isooctyl poly(ethylene oxide) ether poly(propylene oxide) ether sulfate(i-OEPS) and sodium isooctyl poly(propylene oxide) ether poly(ethylene oxide) ether sulfate(i-OPES),were synthesized through such steps as alkoxylation,sulfation of SO3 vapor and neutralization of sodium hydroxide in the case that isooctanol was utilized as an initiator. Furthermore,their physical and chemical properties were characterized by static surface tension, contact angle,and salt tolerance. The product structures were characterized by FTIR and 1H NMR. Characterization results showed that hydroxyl had been substantially replaced by sulfate, successfully obtaining the desired product. The experimental results showed that with isooctyl as the hydrophobic chain,the embedding of oxypropylene group could significantly reduce the critical micelle concentration of surfactants. i-OEPS could diffuse to gas-liquid and gas-solid interfaces more easily than i-OPES,thus rapidly decreasing surface tension. At 25 ℃,150 mmol/L of i-OEPS and i-OPES droplets were able to spread rapidly on the parafilm and the equilibrium contact angle decreased to 58° and 62° in 5 s,respectively. The tolerance of 1.0%(w) i-OEPS and i-OPES aqueous solutions to NaCl,CaCl2and MgCl2were 157.2,213.9,275.0 g/L and 168.3,226.8,205.6 g/L.%以异辛醇为起始剂,经过烷氧基化、气体SO3硫酸化和氢氧化钠中和等步骤,得到表面活性剂异辛基聚氧乙烯醚聚氧丙烯醚硫酸钠(i-OEPS)和异辛基聚氧丙烯醚聚氧乙烯醚硫酸钠(i-OPES),并研究了表明活性剂水溶液的静态表面张力、接触角和耐盐性等物化性能.采用FTIR和1H NMR对产物结构进行了表征.表征结果显示,羟基已基本被硫酸酯基所取代,成功得到了目标产物.实验结果表明,以异辛基为疏水链时,嵌入氧丙烯基可显著降低表面活性剂的临界胶束浓度;i-OEPS比i-OPES容易扩散至气液和气固界面,进而快速降低表面张力;25 ℃时,150 mmol/L的i-OEPS和i-OPES液滴在石蜡膜上可快速铺展,平衡接触角在5 s内分别降低至58°和62°;1.0%(w)的i-OEPS和i-OPES水溶液对NaCl,CaCl2,MgCl2的耐受性分别可达157.2,213.9,275.0 g/L和168.3,226.8,205.6 g/L.
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