聚丙烯酸酯微乳液平均粒径影响因素的研究

Study of factors that affect average particle size of polyacrylate microemulsion

探讨了利用预乳化种子法合成聚丙烯酸酯微乳液的聚合过程中,去离子水用量、阴离子与非离子乳化剂配比及用量、聚合温度、功能性单体用量及混合单体配比对平均粒径的影响。结果表明,在反应过程中,控制去离子水用量为总质量的60%、乳化剂十二烷基硫酸钠(SDS)和壬基酚聚氧乙烯醚(OP-10)质量比为4∶1及复合乳化剂的用量为总质量的3%～5%时,合成的微乳液粒径小、分布好;聚合温度对聚丙烯酸酯微乳液平均粒径的影响较小;随功能性单体甲基丙烯酸用量的增加,微乳液平均粒径增大明显,其加入量以不超过总质量的1.8%为宜;当甲基丙烯酸甲酯(MMA)的用量等于或大于丙烯酸丁酯(BA)的用量时,可得到纳米级微乳液。

In the polymerization process for preparing polyacrylate microemulsion using pre -emulsification seed polymerization method, factors that affect the average particle size of the microemulsion, such as dosage deionized water, ratio of anionic surfactant to nonionic surfactant, polymerization temperature, dosage of functional monomer and ratio of soft monomer to hard monomer were discussed. Results showed that in the reaction process, when the dosage of deionized water is controlled as 60% of the total amount of reactants ; the ratio of emulsifier sodium dodecyl sulfate to poly -ethoxlated nonylphenol （OP- 10） is 4：1 and the dosage of blended emulsifier is 3% -5% of the total amount of reactants,the average particle size of the prepared microemulsion achieves a small value and the distribution is in a good manner. Effect of polymerization temperature on the average particle size is rather small. Following the increase of dosage of functional monomer methyl acrylic acid, the average particle size increases significantly. It is suggested that the dosage should be not over 1.8% （w） of the amount of total reactants. When the dosage of methyl methacrylate is not less than that of butyl acrylate, nanosized microemulsion can be obtained.