以α,ω-二溴代烷、丁基咪唑和三丁基膦为原料经过二步反应合成了3种Bola型非对称阳离子表面活性剂。中间体1-(12-溴十二烷基)-3-丁基咪唑溴盐的较佳合成工艺条件为:n(丁基咪唑)∶n(1,12-二溴十二烷)∶n(四丁基碘化铵)=1∶1.5∶0.005,异丙醇作溶剂,反应温度65℃,反应时间6 h;Bola型表面活性剂的合成工艺条件为:n(1-(12-溴十二烷基)-3-丁基咪唑溴盐)∶n(三丁基膦)=1.05∶1,微波辅助反应,反应温度80℃,反应时间12 h。所合成的Bola型表面活性剂表现出了优良的表面活性,30℃时cmc在5.7×10^-3~8.7×10^-2mol·L^-1之间、γcmc在30~36 m N·m^-1之间;随着碳链长度的增长,其cmc,γ_cmc及分子最小横截面积(A_min)逐渐减小,饱和吸附量(Γ_max)和吸附效率(pc_20)逐渐增大。
The structure of a room temperature asymmetrical dicationic ionic liquid (ADIL), 1-(pyridinium-l-yl) propane- (1-methylpiperidinium) bi[bis(tfifluoromethanesulfonyl)imide] ([PyC3Pi][NTf2]2), was studied by the X-ray difo fraction method. Meanwhile, thermal analysis of [PyC3Pi][NTf2]2 was also studied using non-isothermal thermo- gravimetric analysis (TGA). The title crystal belongs to the triclinic with space group Pi and unit-cell parameters a : 0.95217 (8) nm, b = 1.05129 (11 ) nm, c = 1.70523 (14) nm, ct = 89,759 (8)°,β = 80.657 (7)°, γ=68.007 (9)°, and F(000) = 792. Thermal stability and thermal decomposition kinetics of the title compound were also investigated using TGA under the atmosphere of highly pure nitrogen. Heating curves at different rates were cor- related with kinetic equations Friedman and ASTM (also called iso-conversion method). The values of average activation E (kJ·mol^-1 ) and pre-exponential constant lgA are 149.58 kJ. mol- 1 and 8.83, respectively, which were obtained by the two methods. The kinetic model function, activation energy and pre-exponential constant of this reaction using the multivariate non-linear-regression method were f(a) = (1 -a)(1 + 4.1870a), 151.04 kJ·mol^-1 and 8.81, respectively, which were basically consistent with iso-conversion methods.
Jun WangManman WangXuzhao YangWenyuan ZouXiang Chen