居贝特十四醇聚氧乙烯醚羧酸钠盐的合成及表面性能

Synthesis and Surface Activity of Sodium Guerbet Tetradecyl Polyoxyethylene Ether Carboxylates

以正庚醇为起始原料,经过Guerbet、Williamson等一系列反应合成出了具有支链结构的居贝特十四醇聚氧乙烯醚羧酸钠盐[C14GA(EO)nCH2COONa,n=1-4]。用IR、NMR测定了所合成的表面活性剂的结构;用滴体积法测定了其表面张力。结果表明:该类表面活性剂有比较好的表面性能,并且随着分子中氧乙烯(EO)单元数的增多,该系列表面活性剂[C14GA(EO)nCH2COONa,n=1-4]的临界胶团浓度(CMC)以及临界胶团浓度时的表面张力(γCMC)降低,分别为:10．50 mmol/L,27．87 mN/m;0．85 mmol/L,26．00 mN/m;0．75 mmol／L,25．20 mN/ m:0．59 mmol/L,25．18 mN/m。讨论了该类表面活性剂的结构与表面活性的关系。

A series of double tail surfactants sodium Guerbet tetradecyl polyoxyethylene ether carboxylates [ C14 GA ( EO)nCH2COONa, n=1-4] were synthesized from n-heptanol by Guerbet reaction and Williamson reaction. The chemical structures of these surfactants were identified by IR and NMR. The surface tensions of water solution of these surfactants were determined by drop-volume method. The results showed that with increasing number of EO ( from 1 to 4) , both the critical micelle concentration (CMC) and surface tension ( γCMC ) of these surfactant C14 GA ( EO)nCH2COONa [respectively 10. 50 mmol/L,27. 87 mN/m;0. 85 mmol/L,26. 00 mN/m;0. 75 mmol/L,25. 20 mN/ m;0. 59 mmol/L,25. 18 mN/m] decreased. The relationship between structure and surface activity of this group of surfactants was discussed.