微波辐射丙烯酸酯乳液聚合动力学研究

Kinetics on Polymerization of Acrylic Ester Emulsion by Microwave Irradiation

利用Discover微波精确有机合成系统,以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)为聚合单体、过硫酸钾(KPS)为引发剂、十二烷基硫酸钠(SDS)为乳化剂进行乳液聚合。考察了微波辐射功率对乳液聚合反应的影响,分别考察了引发剂的质量,乳化剂质量,甲基丙烯酸甲酯质量,丙烯酸丁酯质量及反应温度,还对微波聚合反应动力学方程进行了研究。利用热重分析仪,差示扫描量热仪和傅立叶变换红外光谱仪对聚合物乳液的性能进行了测试与结构表征。实验结果表明,反应体系选择60 W为微波辐射条件,m(KPS)为0.06 g、m(SDS)为0.27 g、m(MMA)和m(BA)均为3 g,反应温度为343 K,测得聚合反应的活化能Ea=96.957 1 kJ/mol,建立了单模聚焦微波辐射乳液聚合的动力学方程:Rp=k[n(KPS)]1.107 9[n(SDS)]0.616 4[n(MMA)]1.205 9[n(BA)]-0.228。

Acrylic ester emulsion was polymerized in the Discover Organic Synthesizing System with methyl methacrylate （MMA） and butyl acrylate（BA） as polymerizing monomer, potassium peroxydisulfate （KPS） as evocating agent, and sodium dodecyl sulfate （SDS） as emulsifier. In the process the mass of KPS, SDS, MMA and BA, as well as reaction temperature were separately inspected in detail so that the influence of microwave power on emulsion polymerization and a kinetic study of microwave polymerization had been conducted. The property and structure of polymerization emulsion was determined and characterized with thermogravimetrie analyzer（TGA）,differential scanning calorimeter（DSC） and FT-IR. The results of the experiments show that microwave power is 60 W, the mass of KPS, SOS, MMA and BA is 0.06 g, 0.27 g , 0.3 g and 0.3 g respectively; reaction temperature is 343 K; the activation energy of reaction is Ea = 96. 957 1 kJ/mol the kinetics equation, Rp =k [n （KPS）]^1.1079 In （ SDS）]^0.6164[n （ MMA）]^1.2059 [n （BA）] 0.228 is established for single mode focusing microwave irradiation emulsion polymerization.