【摘要】 研究在真空密闭、存在脱水剂的条件下聚乳酸固相缩聚工艺的可行性,得到了分子量达25万的聚乳酸;实验研究了催化剂浓度,预聚体粒度和反应时间对缩聚过程的影响,表明降解副反应仍然是控制聚乳酸最终分子量的重要因素。更多还原

【Abstract】 An innovative process for the production of high molecular weight poly(L-lactic acid)(PLLA) was presented, featuring solid-state polycondensation of L-lactic acid(LA) in a closed system with a dehydrant to remove water selectively. The final PLLA obtained has a molecular weight of 250000. The influences of different operating variables on the changes of molecular weight, as well as the highest molecular weight attainable were investigated experimentally, which reveals that thermal degradation is still the most important factor that controls the molecular weights of PLLA products.更多还原