甲基丙烯酸甲酯反相微乳液聚合研究

Study on Methyl Methacrylate Polymerization in Inverse Microemulsions

绘制了甲基丙烯酸甲酯(MMA)/丙烯酸(AA)/十二烷基硫酸钠(SDS)-H2O拟三元相图,确定了不同类型微乳液区域;采用偶氮二异丁腈(AIBN)引发MMA/AA/SDS/H2O反相微乳液聚合,得到了具有明显孔穴结构的聚合物;研究了反相微乳液体系的聚合动力学,考察了AIBN用量、AA含量、SDS水溶液含量及反应温度对初期聚合速率(dC/dt)的影响,得到dC/dt∝[AIBN]0.8[AA]1.2[W]0.7,聚合表观活化能为93.8kJ/mol,并提出了“微乳液双相聚合”的概念.

The pseudo-ternary phase diagram of methyl methacrytate （MMA）/acrylic acid（AA）/ sodium dodecyl sulfate （SDS）/water system was figured out. The single-phase region was partitioned into inverse, bicontinuous and direct microemulsion areas with conductivity measurements. The polymerization in the inverse microemulsions was initiated by azobisisobutyronitrile （AIBN） and microporous polymer was obtained. The kinetic study of the inverse microemulsion polymerization was further carried out and the concept of biphase polymerization was introduced. The effects of the amount of initiator, the content of AA, the content of SDS aqueous solution and reaction temperature on the polymerization rate at 5% conversion were investigated, and the following relation was obtained： dC/dt∝[AIBN]^0.8[AA]^1.2[W]^0.7 The exponent expressing dependence on initiator was 0. 8, which meant that monoradical termination was perhaps the dominant termination manner. In addition, the apparent total active energy of the inverse microemulsion polymerization was 93.8kJ/mol.