酯基型双子表面活性剂的合成及驱油性能

Synthesis and Oil Displacement Performance of Gemini Surfactants with Ester Group

采用丁二酸酐、N,N-二甲基乙醇胺和溴代烷C_nH_(2n+1)Br(n=10、12、14、16、18)通过两步反应制备了含酯基的阳离子双子表面活性剂[简称为GSn-EG-n(n=10、12、14、16、18)]。利用FTIR、~1HNMR对GS14-EG-14结构进行表征,用表面张力仪、电导率仪、荧光光谱仪(FLD)、光学接触角测量仪和界面张力仪对GSn-EG-n的溶液性质进行测定。结果表明,随着碳链长度的增加,表面活性剂越易聚集缔合成胶束,GS18-EG-18临界胶束浓度(CMC)最低达到2.14×10^(-5)mol/L,GS14-EG-14溶液的表面张力最低降至33.50 m N/m。通过测定不同温度下溶液的电导率,发现其电导率随着温度的升高而增大。乳化性和润湿性测试结果表明,GS14-EG-14乳化系统中,油/水分离时间达到180 min,且在聚四氟乙烯板(简称PTFE)上的接触角为69.3°,说明GS14-EG-14具有很好的乳化性能和润湿性能。GS18-EG-18仅用28 min可以将油/水界面张力降低至8.6×10^(-3)m N/m。GSn-EG-n的最终驱油效率达54.2%。

A series of biquaternary ammonium salt gemini surfactants with ester group（denoted as GSnEG-n,n=10,12,14,16 and 18）were prepared with succinic anhydride,N,N-dimethylethanolamine and bromoalkanes（CnH（2n＋1）Br,n=10,12,14,16 and 18）as raw materials.The structure of GS14-EG-14 was characterized by FTIR and^1HNMR.The solution properties of GSn-EG-n were investigated using surface tensiometer,conductivity meter,fluorescence spectrometer（FLD）,optical contact angle measuring device and interface tensiometer.The results showed that with the increase of hydrophobic chain length,the surfactants were easier to associate and form micelles,and the critical micelle concentration（CMC）of GS18-EG-18 decreased to 2.14×10^（-5）mol/L.The minimum surface tension（γ（CMC））of GS14-EG-14 was 33.50 m N/m.Moreover,by measuring the conductivity of GSn-EG-n solution at different temperature,it was found that the CMC value of solution increased with the increase of temperature.The emulsification and wettability tests demonstrated that GS14-EG-14 gave a oil/water separation time of 180 min,and the contact angle of solution of GS14-EG-14 on polytetrafluoroethylene（PTFE）was 69.3°,indicating that GS14-EG-14 possesssed excellent emulsifying power and wetting property.Besides,GS18-EG-18 could make the oil/water interfacial tension reduce to 8.3×10^（-3）m N/m within 28 min,and its final oil displacement efficiency was 54.2%.