【作者】 尤丽莎；

【导师】 吴华强； 魏先文；

【作者基本信息】 安徽师范大学 ， 物理化学， 2002， 硕士

【摘要】 用无皂乳液聚合的方法制备的高分子纳米胶乳粒子表面洁净，分散均匀，有很好的粘接性和抗水性，在生物体系中亦有广泛的应用。由于微波辐照制备稳定的无皂高分子纳米粒子与常规无皂乳液聚合相比，具有速率快，制备的粒子粒径小，粒径分布窄的优点，本论文工作主要利用常压微波辐照下无皂乳液聚合的方法合成高分子微球。并且通过对无皂乳液聚合中聚合单体、助溶剂、引发剂、反应温度等因素对聚合反应动力学及所得高分子微球的粒径、粒径分布影响的系统研究，探讨了制备稳定的均分散无皂纳米胶乳粒子的条件，并对所制备的无皂胶乳进行了常温贮存稳定性、低温贮存稳定性以及电解质稳定性的测试。 通过分析各种因素对无皂聚合反应的影响，并对反应过程中的转化率、透光率、体系中的粒子平均水化半径及粒径分布的测定，深入探讨了丙酮-微波法合成无皂高分子共聚胶乳粒子机理，认为在微波辐照和助溶剂丙酮的存在下，无皂共聚胶乳粒子的成核机理为“均相成核”与“胶束成核”并存，而且随着反应的进行存在“多次成核”。同时也探讨了微波辐照下丙酮-水体系无皂聚苯乙烯胶乳粒子、甲醇-水体系无皂聚苯乙烯和苯乙烯与甲基丙烯酸甲酯共聚胶乳粒子的形成机理。更多还原

【Abstract】 The latexes obtained by emulsifier-free emulsion polymerization show good adhesion and water-resistant properties and are characterized by having a narrow size distribution and ’clear’ surface. They had been widely applied in biological systems.Emulsifier-free macromolecule nanoparticle latex can be obtained by conventional heating method but the reaction takes more time and the particle size distribution is wide in comprision with those obtained by microwave heating method. So in this paper, the monodisperse emulsifier-free macromolcule nanoparticle latex is obtained by the use of microwave radiation under ambient pressure. The suitable condition for the preparation of such latex is discussed through analyzing the factors such as the kind and content of monomer, cosolvent, initiator and the temperature of the reaction. The stability testing of the synthesized latex such as the storage stability at normal or low temperature and the stability to electrolyte is done.The particle formation mechanism of emulsifier-free macromolecule nanoparticles under microwave radiation is discussed through analyzing several kinds of factors affecting the emulsifier-free polymerization and the data or phenomena obtained during the polymerization such as the curve of the conversion vs. time, the curve of the transparency of the system vs. time, the hydrodynamic radius and its distribution during the polymerization. It is considered that both the homogeneous nucleation and the micelle nucleation exist in acetone-water medium or in methanol-water system. Furthermore, the nucleation will happen several times during the polymerization.更多还原