中文摘要：

采用分散聚合和无皂乳液聚合的方法,我们制备了粒径不同的交联聚合物微球。通过改变超临界二氧化碳的压力、处理微球的时间以及实验的温度,我们可以实现对这些微球塑化程度的调节。研究发现,随着超临界二氧化碳压力的升高,其对聚合物微球的塑化能力呈现出先增强后降低的趋势。文中我们对这种现象出现的机理也进行了相应的讨论。随着体系温度的升高或者延长处理微球的时间,超临界二氧化碳对两种微球的塑化能力都呈增强趋势。由于乳液聚合得到的聚合物的分子量通常会比分散聚合得到的聚合物的分子量大,因此在相同的条件下超临界二氧化碳对分散聚合法制备的微球塑化能力更强。

英文摘要：

Cross-linked polymer microspheres with different sizes were fabricated by dispersion polymerization and emulsifier-free emulsion polymerization methods.Through changing the pressure,the time and the temperature of supercritical carbon dioxide,we could tune the plasticization degree of these particles.The results illustrate that with the increase of pressure,the plasticization ability of supercritical carbon dioxide to polymer microspheres increased first and then decreased.The mechanism of the appearance of the phenomenon was discussed in the paper.Through increasing the temperature or prolonging the time,the plasticization ability of supercritical carbon dioxide to the two kinds of polymer microspheres could be enhanced.Due to the molecular weight of the polymer obtained by emulsion polymerization method usually is bigger than that obtained by the dispersion polymerization method,the plasticization ability of supercritical carbon dioxide to the polymer microspheres fabricated by dispersion polymerization method was stronger at the same condition.