Abstract: An antisolvent，absolute ethyl alcohol was used in the high-voltage electrostatic antisolvent process to prepare poly (L-lactide) microspheres. A 24 factorial experiment was designed to investigate and identify the relative significance of the processing parameters on particle size and particle size distribution of the products. The results indicated that the effect of push speed was dominant in the results regarding particle size. After optimization，the resulting poly (L-lactide) microspheres exhibited good spherical shape，smooth surface and narrow particle size distribution. When the concentration and molecular weight of poly (L-lactide) were 3% (w/v) and 50～100 kDa respectively，the resulting microspheres showed good spherical shape. Fourier transform infrared (FTIR) spectroscopy measurement found no significant structural perturbation. X-ray powder diffraction (XRPD) analysis revealed no significant crystal structural changes.

Key words: high-voltage eletrostatic system, anti-solvent, poly (L-Lactide), factorial experiment

摘要： 以无水乙醇为非溶剂，采用高压静电抗溶剂法制备聚乳酸微球。通过24全因子试验设计对微球粒径和粒径分布的影响因素进行了显著性分析。并考察最显著因素对微球表面形貌的影响规律。结果表明，推进速度是影响微球粒径的最显著因素，最优条件下微球表面光滑、球形度好，粒径分布窄。浓度为3%，相对分子质量为5万～10万的聚乳酸制备的微球，球形度较好。经过高压静电处理后，傅里叶红外光谱测定表明聚乳酸无明显结构摄动；X射线粉末衍射分析表明聚乳酸晶体结构未发生明显变化。

关键词: 高压静电体系, 抗溶剂, 聚乳酸, 因子试验