【摘要】 采用溶剂热法,以丙酮-水为混合溶剂,过硫酸钾(KPS)为引发剂引发甲基丙烯酸甲酯(MMA)和苯乙烯(St)共聚,制得了粒径约为31 nm的共聚无皂纳米粒子。系统地探讨了温度、丙酮含量、单体比和引发剂浓度对聚合速率、粒子粒径、单分散性和乳液稳定性的影响。结果表明,随着温度的升高,粒径先减小后增大,在90℃时出现最低值;随着丙酮含量和MMA/St比例的增加,粒径由267 nm减小到34 nm,乳液稳定性提高,反应后期转化速率随丙酮含量的增加而明显下降;随着KPS浓度的增加,粒径先减小后增大。更多还原

【Abstract】 Emulsifier-free poly(styrene-methylmethacrylate)(P(St-MMA)) copolymer nanoparticles with an average diameter of about 31 nm were synthesized in an acetone-water medium with potassium persulfate(KPS) as the initiator by solvothermal method.The effects of amount of acetone,MMA/St ratio,the concentration of KPS and temperature on the polymerization rate,the particle size and the size distribution as well as the stability of the latex were investigated systematically.The results indicate that with(increasing) temperature,the particle size decreases first,and then increases and reaches a minimum at 90 ℃;with increasing the(volume) fraction of acetone or the volume ratio of MMA to St,the particle size decreases from 267 nm to 34 nm and the electrolyte-resistance stability of the latex increases;the polymerization rate in the last(reaction) stage falls down on(increasing) the volume fraction of acetone;with increasing the KPS concentration,the particle size decreases first and then increases.The solvothermal mothod has offered a new route to emulsifer-free(macromolecule) nanoparticles.更多还原