甲基丙烯酸甲酯可聚合微乳液体系的研究

分别采用电导率仪、粘度计和折射仪测定了不同类型微乳液的结构变化.结果表明,在固定甲基丙烯酸甲酯(MMA)/丙烯酸(AA)混合单体量的情况下,随着水相含量的增加,体系的电导率、粘度和折射率发生明显变化,体系由反相微乳液经双连续型微乳液逐渐转变为正相微乳液.对微乳液的粒度分析表明,油相含量较低时,正相微乳液体系中的液滴可视作溶胀胶束;在反相微乳液中,随着十二烷基硫酸钠水溶液含量的增加,水相液滴粒径明显增大;在MMA/AA/H2O无皂反相微乳液体系中,微乳液的粒子比有皂体系的大.最后,微乳液聚合表明过硫酸钾能够稳定引发正相微乳液聚合,同时Mn3+也可用于引发正相微乳液聚合.

Study on polymerizable microemulsion systems containing methyl methacrylate

The variation in structure of microemulsion was measured by conductometer, viscosimeter and refractometer. The results showed that the conductivity, viscosity and refractive index of microemulsion systems changed with increasing the aqueous phase when the amount of methyl methacrylate(MMA)/ acrylic acid (AA) mixed monomers was fixed, and indicated that the system changed from W/O microemulsion through bicontinuous microemulsion to O/W microemulsion. The particle analysis showed that the particles were regarded as swollen micelles with reason in O/W microemulsion with low amount of oil phase, the particle size was enlarged with increasing the amount of sodium dodecyl sulphate (SDS) aqueous solution in W/O microemulsion, and the particles in MMA/AA/H_2O soap-free inverse microemulison was obviously larger than those in MMA/AA/SDS/H_2O inverse microemulison. Finally, polymerization in O/W microemulsions was investigated. It was found that potassium persulfate was suitable to initiate polymerization stably, while manganese pyrophosphate was also able to initiate polymerization.