低温氧化还原引发体系的PU/MMA-BA超浓乳液共聚合  

Concentrated emulsion copolymerization of PU /MMA -BA initiated by redox system at low temperature

作　　者：张洪涛[1] 王岸林[1] 陈敏[1] 操建华[1] 

机构地区：[1]湖北大学化学与材料科学学院,湖北武汉430062

出　　处：《合成橡胶工业》2003年第5期274-279,共6页China Synthetic Rubber Industry

基　　金：国家自然科学基金资助项目(29974007)。

摘　　要：以十二烷基硫酸钠和十六烷醇为复合乳化体系,过硫酸铵/亚硫酸氢钠为氧化还原引发体系,在低温下引发PU/MMA-BA超浓乳液共聚合。研究了复合乳化剂质量浓度、氧化还原引发剂质量浓度、内相比、聚合温度等因素对聚合稳定性和聚合速率的影响,观察了聚合物胶乳粒子的形态,并测试了聚合物胶乳粒子粒径及其分布。结果表明,最佳聚合工艺是PU预聚体中—NCO/—OH(质量比)为1.5～2.0,PU/MMA-BA(质量比)为1/4～1/3,复合乳化剂质量浓度为0.06～0.15g/mL,氧化还原引发剂质量浓度为0.025g/mL,氧化剂/还原剂(摩尔比)为1/0.830～1/0.710,内相比为0.80,聚合温度为20～40℃;聚合反应5h后,单体转化率超过90%,制得了粒径为200nm左右、分散度为0.100～0.400的PU/MMA-BA胶乳粒子。The stable concentrated emulsion o f PU prepolymer /methyl methacrylate-butyl acrylate(PU /MMA -BA)was prepared using sodium do-decyl sulfate and cetyl alcohol as th e compound surfactants,ammonium persulfate /sodium hydrosul-fite as redox initiators at low temperature.The influ-ences of mass concentration of compound surfactant,mass concentration of redox system,interior phase ratio,polymerization temperature on polymerization stability and conversion of PU /MMA -BA emulsion were investigated.The particle dia meter,distribution of particle diameter and morphology of PU /MMA -BA emulsion were determined respectively.The results showed that the optimum cond itions were-NCO /-OH(mass ratio)of polyurethane pre-polymer 1.5～2.0,PU /MMA -BA(mass ratio)1/4～1/3,mass concentration of comp ound surfac-tant 0.06～0.15g /mL,mass concentra tion of redox system 0.025g /mL,oxidant /reducer(molar ratio)1/0.830～1/0.710,interior phase ra tio 0.80,polymerization temperature 20～40℃.The final conversion was more than 90%after re acting 5h,and PU /MMA -BA emulsion with particle diameter200nm and dispersibility 0.100～0.400were pre-pared.

关 键 词：聚氨酯预聚体 甲基丙烯酸甲酯 丙烯酸丁酯 超浓乳液聚合 氧化还原引发体系 聚合稳定性 聚合动力学 

分 类 号：TQ316.3[化学工程—高聚物工业]