Wang N, Wu X S, Lujan-Upton H, Donahue E, Siddiqui A
Division of Pharmaceutics and Industrial Pharmacy, Arnold & Marie Schwartz College of Pharmacy and Health Sciences, Long Island University, NY 11201, USA.
J Biomater Sci Polym Ed. 1997;8(12):905-17. doi: 10.1163/156856297x00083.
A series of oligomers or low molecular weight polymers of lactic and/or glycolic acid has been synthesized with different molar ratios of lactic to glycolic acid. These oligomers have been characterized with respect to oligomer composition, molecular weight, intrinsic viscosity, crystallinity, melting temperature, and glass transition temperature. The polymerization conditions for the lactic/glycolic acid oligomer syntheses were as follows: 180-220 degrees C, 5 mm Hg, 5 h, and 0.1 wt% of catalyst (antimony oxide) concentration. The polymeric compositions correlated to the feed ratios of lactic to glycolic acid. The molecular weight of the oligomers ranged from 895.8 +/- 48.7 to 1368.0 +/- 0 D with the intrinsic viscosity ranging from 0.0513 to 0.0814 dl g-1. The lactic/glycolic acid oligomers were found to be amorphous. The glass transition temperatures of the lactic/glycolic acid oligomers were lower than physiological temperature.
已经合成了一系列具有不同乳酸与乙醇酸摩尔比的乳酸和/或乙醇酸低聚物或低分子量聚合物。这些低聚物已在低聚物组成、分子量、特性粘度、结晶度、熔点和玻璃化转变温度方面进行了表征。乳酸/乙醇酸低聚物合成的聚合条件如下：180 - 220摄氏度、5毫米汞柱、5小时以及0.1重量%的催化剂（氧化锑）浓度。聚合物组成与乳酸和乙醇酸的进料比相关。低聚物的分子量范围为895.8±48.7至1368.0±0道尔顿，特性粘度范围为0.0513至0.0814分升/克。发现乳酸/乙醇酸低聚物为无定形。乳酸/乙醇酸低聚物的玻璃化转变温度低于生理温度。
