文章采用熔融共混和反应挤出技术制备改性聚乙醇酸（PGA）。研究扩链剂、交联剂和润滑剂对PGA熔体流动性、动态流变性能、热稳定性、结晶性能的影响。结果表明：ADR扩链剂和BIBP交联剂共同作用可提升PGA熔体强度，熔体质量流动速率较纯PGA下降73.6%，同时改善PGA的热稳定性，5%热分解温度提高7 ℃。分别添加ADR扩链剂和BIBP交联剂，降低PGA结晶度，减少PGA晶核数量，同时增加球晶尺寸。添加扩链剂和交联剂，二者共同作用，增加PGA分子交联程度，结晶不完善，形成不规则晶粒。润滑剂促进分子运动，PGA的结晶温度从未添加润滑剂的179.3 ℃降至添加润滑剂后的173.9 ℃。

Modified polyglycolic acid (PGA) was prepared by melt blending and reactive extrusion. The effects of chain extenders, crosslinking agents and lubricants on melt fluidity, dynamic rheological properties, thermal stability, and crystallization properties of modified samples were studied. The results show that the melt strength of samples are significantly improved by using ADR chain extender and BIBP crosslinking agent simultaneously, the melt mass flow rate is decreased by 73.6% compared to pure PGA. The thermal stability of modified samples is also improved, with increasing the 5% thermal decomposition temperature by 7 ℃. With the addition of chain extender and crosslinking agent, the degree of crystallinity of PGA samples are decreased, the number of crystal nuclei are decreased, and the spherulite size are increased. The degree of cross-linking of the sapmles with adding chain extender and crosslinking agent at the same time is increased, resulting in imperfect crystallization and the formation of irregular crystals. Molecular motion are promoted by lubricants, and the crystallization temperature of PGA sample is decreased from 179.3 ℃ without addition to 173.9 ℃ after addition.