摘要
讨论了MMA-St无皂乳液聚合,当[KPS]=2.77×10^(-3)mol/L,[MMA]0.51mol/L,[St]=0.49mol/L,70℃反应5.0小时,能得到较高的聚合转化率,较小的胶乳粒径和较大的粒子浓度,并对不同反应时期聚合物的分子量及其分布进行了测定,认为该无皂乳液聚合体系为均相沉淀成核机理。当转化率大于30.9％时,胶乳粒的凝聚程度大于胶乳粒的生成速度。KPS分解产生的自由基起到了稳定乳液的作用。
The emulsifier-free emulsion copolymerization of MMA with St has been carried out. At 70℃, [KPS]= 5. 55×10^(-3)mol/L, [MMA]= 0. 51mol/L and [St]=0. 49mol/L a higher conversion, smaller emulsion particles and greater concentration of particles can be obtained. A homogeneous nucleation mechanism has been proposed on the basis of the molecular weight and its distribution measurements in the course of the copolymrization . When the value of conversion exeessed 30. 9%, the agglutination degree of the emulsion particles surpassed the formation speed of the particles. Radicles formed from KPS on decomposition appeared to stabilize the emulsion.
出处
《应用化学》
CAS
CSCD
北大核心
1993年第4期51-54,共4页
Chinese Journal of Applied Chemistry
关键词
甲基丙烯酸酯
无皂乳液聚合
methyl methacrylate ,styrene,emulsifier-free emulsion copolymerization ,nucleation mechanism
