双子表面活性剂N,N′-双十二烷基对苯二甲胺丙酸的合成及性能研究

摘要

Gemini surfactant N,N′-bis(dodecyl)-1,4 -xylylene diamine propionate acid was synthesized from dodecylamine,methyl acrylate and p-xylylene dichloride as starting materials with trichloromethane as solvent. The chemical structure of the product was characterized by 1 H NMR and 13 C NMR. Performance of the product at (25 ± 1 )℃ were studied and the results show that when the pH value is separately prepared at 8 , 10 and 12 ,the critical micellar concentration (cmc ) is 1. 6 × 10 -5 ,3. 3 × 10 -5 and 2. 1 × 10 -5 mol/L respectively;the surface tension (γcmc )is 32. 39,33. 24 and 36. 94 mN/ m;the pc 20 is 2. 56,2. 14 and 2. 09;the Γmax is 3. 45 × 10-6 ,3. 97 × 10-6 and 4. 34 × 10-6 mol/ m2;the A min is 0. 48,0. 42 and 0. 38 nm2 . When the pH value rises to 12,following the raise of temperature,the values of pc 20 and Amin increase but the Γmax decreases.%以十二胺、丙烯酸甲酯和对二氯苄为原料,三氯甲烷为溶剂,合成了双子表面活性剂N,N′-双十二烷基对苯二甲胺丙酸.采用1 H NMR和13 C NMR对其结构进行了表征.(25±1)℃时pH对产物表面活性的影响研究结果表明:pH分别为8,10和12时,cmc分别为1.6×10-5,3.3×10-5和2.1×10-5 mol/L;γcmc分别为32.39,33.24和36.94 mN/m;pc 20分别为2.56,2.14和2.09;Γmax分别为3.45×10-6,3.97×10-6和4.34×10-6 mol/m2;A min分别为0.48,0.42和0.38 nm2.当pH=12时,随溶液温度升高,pc 20和A min增大,Γmax减小.