摘要
以十二胺和甲基丙烯酸甲酯为原料,通过两步反应合成了一种pH响应性氨基酸两性表面活性剂——N-月桂基-(α-甲基)-β-氨基丙酸钠(AAS-1)。采用单因素实验进行了反应条件优化,得出最优工艺条件为:n(十二胺)∶n(甲基丙烯酸甲酯)=1.0∶1.4,反应温度为60℃,反应时间为10 h。以同样的方法合成了表面活性剂N-月桂基-β-氨基丙酸钠(AAS)作对比实验。采用FTIR和~1HNMR对产物结构进行了表征,用表面张力仪测定了不同pH下AAS和AAS-1的表面张力,得出表面张力曲线,并着重考察了α-烷基对AAS-1表面活性的影响。用WaringBlender法对AAS和AAS-1在不同pH下的泡沫性能进行了测定。结果表明:AAS和AAS-1均具有pH响应性。受α-烷基的影响,pH<7时,AAS-1的泡沫体积(V_0)最高可达523 mL,泡沫半衰期(t_(1/2))最高可达6.25 min;pH>7时,AAS-1的V_0<185 mL,t_(1/2)<0.58 min,说明AAS-1在酸性水介质中,起泡能力强,泡沫稳定性好;在碱性水介质中却可迅速消泡,与AAS的发泡规律恰好相反,且能反复起泡消泡,可用于泡沫酸液体系中充当起泡剂。
A pH-responsive amino acid amphoteric surfactant,N-lauryl-(α-methyl)-β-aminopropionate(AAS-1)was synthesized by two-step reaction using dodecylamine and methyl methacrylate as raw materials.The synthesis conditions were optimized by single factor experiments.The optimal synthesis conditions were obtained as follows:molar ratio of dodecylamine to methyl methacrylate was 1.0∶1.4,reaction temperature was 60℃,and reaction time was 10 h.For comparison,N-lauryl-β-aminopropionate(AAS)was prepared in the same way.The structures of products were characterized by FTIR and 1HNMR.The surface tensions of AAS and AAS-1 at different pH were measured by surface tension meter,and the surface tension curves were achieved.Furthermore,the effect ofα-alkyl on the surface activity of AAS-1 was investigated.Foam properties of AAS and AAS-1 at different pH were tested by Waring Blender method.The results showed that both AAS and AAS-1 had pH responsiveness.Due to the influence ofα-alkyl,when pH<7,AAS-1 had a foam volume(V0)of up to 523 mL and a foam half-life(t1/2)of up to6.25 min,but when pH>7,V0<185 m L,t1/2<0.58 min.This means that,in the acidic aqueous medium,AAS-1 has good foaming ability and good foam stability but can exhibit quick defoaming ability in alkaline water medium,which shows the opposite of AAS foaming regularity.Thus,ASS-1 can be used as foaming agent in the foamed acid system and can be repeatedly foamed and defoamed.
作者
刘佩
赖小娟
王磊
汪洁
马少云
苗林
LIU Pei;LAI Xiao-juan;WANG Lei;WANG Jie;MA Shao-yun;MIAO Lin(Shaanxi Key Laboratory of Chemical Additives for Industry,Shaanxi University of Science&Technology,Xi'an 710021,Shaanxi,China;Shaanxi Research Institute of Agricultural Products Processing Technology,Xi'an 710021,Shaanxi,China;Shanghai Jingma Chemical Co.,Ltd.,Shanghai 201700,China;Xi'an Changqing Chemical Group Co.,Ltd.,Xi'an 710021,Shaanxi,China)
出处
《精细化工》
EI
CAS
CSCD
北大核心
2019年第3期442-448,共7页
Fine Chemicals
基金
陕西省青年科技新星项目(2018KJXX-023)
陕西省教育厅重点实验室项目(17JS012)
西安市科技计划项目(2017068CG)~~
