丙烯酰胺和N,N-二甲基丙烯酰胺反相乳液共聚动力学  

Kinetics of Inverse Emulsion Copolymerization of Acrylamide and N,N-Dimethylacrylamide

作　　者：吴雨晨 陈浩 朱良宇 苗贵兰 龚昀晗 王延梅 WU Yuchen;CHEN Hao;ZHU Liangyu;MIAO Guilan;GONG Yunhan;WANG Yanmei(School of Chemistry and Materials Science,University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]中国科学技术大学化学与材料科学学院,合肥230026

出　　处：《功能高分子学报》2024年第4期332-337,共6页Journal of Functional Polymers

摘　　要：以丙烯酰胺(AM)和N,N-二甲基丙烯酰胺(DMAA)作为单体,失水山梨醇单油酸酯(SPAN-80)为乳化剂,3号白油为连续相,过硫酸铵(APS)和四甲基乙二胺(TEMED)为氧化还原引发体系,通过反相乳液聚合得到AM和DMAA的共聚物,采用核磁共振氢谱对产物进行表征。结果表明,随着投料中n(DMAA)∶n(AM)的增加,聚合速率逐步加快,共聚物中DMAA物质的量多于投料中DMAA的物质的量;聚合速率随时间的变化曲线不存在恒速期,成核机理倾向于单体液滴成核;聚合速率方程为r_(p)=kcM^(1.74)cI^(0.82)cE^(0.77)(其中cM、cI、cE分别为单体总浓度、引发剂浓度和乳化剂浓度),表观活化能为20.53 kJ/mol。The copolymer composed with acrylamide(AM)and N,N-dimethylacrylamide(DMAA)was prepared by using inverse emulsion polymerization with sorbitan monooleate(SPAN-80)as emulsifier,white mineral oil as oil phase,and ammonium persulfate(APS)and tetramethylenediamine(TEMED)as redox initiation systems.The product was characterized by hydrogen nuclear magnetic resonance spectroscopy.Firstly,the relationship between polymerization rate(rp)and monomer feed molar ratio was studied in the range of n(DMAA)∶n(AM)=1∶100 to 1∶25.The results showed that the polymerization rate increased with increasing the DMAA in feed molar ratio and the amount of DMAA structural unit in the resultant copolymer was higher than that in the recipe.By comparing with conventional emulsion polymerization,there was no constant rate period(i.e.,interval II)according to the behavior of polymerization rate versus time,suggesting that the mechanism for particle nucleation(i.e.,formation of polymer particles)might be dominated by monomer droplet nucleation.Then a variety of hehaviors were studied for the polymerization rate versus monomer concentration(cM,14.42—16.00 mol/L),initiator concentration(cI,0.0043—0.0081 mol/L),and emulsifier concentration(cE,0.200—0.234 mol/L)at 296.15 K.The polymerization rate equation was r_(p)=kcM^(1.74)cI^(0.82)cE^(0.77),indicating that monomer concentration had the greatest effect on the polymerization rate among the behaviors investigated.Finally,the apparent activation energy of 20.53 kJ/mol for the inverse emulsion polymerization of AM and DMAA was obtained by Arrhenius formula in the range of 288.15-301.15 K.

关 键 词：动力学 反相乳液 丙烯酰胺 N N-二甲基丙烯酰胺 成核机理 

分 类 号：O63[理学—高分子化学]