脱氢枞酸改性木质素胺乳化剂的合成及其表面活性

摘要

以脱氢枞酸和乙二胺为原料,制备了N-(2-氨乙基)脱氢枞酸酰胺(ADRA),再将ADRA与硫酸盐木质素(KL)、甲醛(F)反应合成了N-(2-氨乙基)脱氢枞酸酰胺/甲醛改性木质素胺(ADRA-F-KL)中间体.探讨了投料摩尔比、反应温度和反应时间对ADRA-F-KL氮含量的影响,并将其进一步与二乙烯三胺(DETA)、甲醛反应,合成了N-(2-氨乙基)脱氢枞酸酰胺-木质素复合阳离子乳化剂(ADRA-DETA-F-KL).实验表明,合成ADRA-F-KL的适宜条件为:反应时间为2.5 h,n(KL)∶n(ADRA)=1∶0.3,反应温度90℃.红外光谱分析、元素分析及表面张力测定结果表明,KL、甲醛与ADRA或DETA经过Mannich反应,在硫酸盐木质素分子结构中引入了相应的胺甲基;目标产物在pH值2.0的稀盐酸溶液中最低表面张力为48.5 mN/m,与未引入N-(2-氨乙基)脱氢枞酸酰胺甲基基团的硫酸盐木质素胺的最低表面张力57.8 mN/m相比较,表面活性得到了较大改善.%The N-(2-aminoethyl) dehydroabietic acid amide (ADRA)was prepared from dehydroabietic acid and 1,2-ethylenediamine. The mediator ADRA-F-KL was synthesized from Kraft lignin( KL), ADRA and formaldehyde (ADRA-F-KL) by mannich reaction. The effects of reaction temperature,reaction time,the molar ratio of reactants on nitrogen contents of ADRA-F-KL were investigated. Cationic composite emulsifier(ADRA-DETA-F-KL) was prepared from ADRA-F-KL, formaldehyde and diethylenetriamine(DETA). The experiments showed that the optimum reaction conditions of ADRA-F-KL were 3h of reaction time, n(KL)∶n(ADRA) = 1∶0.25, 90℃ of reaction temperature. The IR, elemental analysis and surface tension of the target product showed that the corresponding amine-methyl groups were introduced into KL by the Mannich reaction. The minimum surface tension value of ADRA-DETA-F-KL was 48.5 mN/m in dilute hydrochloric acid solution with 2 of pH value. Compared to the lignin modified by diethylenetriamine/formaldehyde whose minimum surface tension is 57.80 mN/m, the surface activity of ADRA-DETA-F-KL is improved greatly.