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以苯乙烯和甲基丙烯酸为单体、PVP为分散剂,AIBN为引发剂,在异丙醇-水介质中,用分散聚合方法制备了微米级单分散的聚(苯乙烯-甲基丙烯酸)[P(St-MAA)]微球。结果表明,采用反应初期低温、中后期升温的聚合工艺可制得单分散的聚合物微球,并提高聚合反应的速率和转化率。P(St-MAA)微球的粒径及其分布可通过改变介质组成来控制。分散介质中异丙醇质量分数降低,聚合反应速率增大,转化率升高,微球的粒径减小。当分散介质中异丙醇的质量分数降低到60%时,聚合反应中有凝胶生成,粒径分布呈多分散性。
With styrene and methacrylic acid as monomer, PVP as dispersant and AIBN as initiator, the monodisperse poly (styrene-methacrylic acid) [P (St-MAA)] microspheres. The results showed that the monodisperse polymer microspheres could be prepared by using the low temperature in the early stage of the reaction and the polymerization in the middle and late stages, and the polymerization rate and conversion rate were improved. Particle size and distribution of P (St-MAA) microspheres can be controlled by changing the medium composition. In the dispersion medium, the mass fraction of isopropanol decreases, the polymerization rate increases, the conversion rate increases, and the particle size of the microspheres decreases. When the mass fraction of isopropanol in the dispersion medium is reduced to 60%, gel formation occurs in the polymerization reaction, and the particle size distribution is polydisperse.