聚羟基乙酸(PGA)分子量测定的方法研究  

Research on the Methods for Determination of Molecular Weight of Poly(glycolic acid)

作　　者：田俊凯[1,2] 崔爱军[1] 陆卫良[1] 朱晔[1] 陈群[1] 何明阳[1] 吴桂宝[1] 王泽云[1] 

机构地区：[1]常州大学江苏省精细石油化工重点实验室,常州213164 [2]南阳师范学院化学与制药工程学院,南阳463000

出　　处：《高分子通报》2012年第8期98-104,共7页Polymer Bulletin

基　　金：江苏省自然科学基金(BK2009543)

摘　　要：基于目前测定聚羟基乙酸(PGA)分子量的常见方法:DMSO重结晶和急速冷却法,分别制得了两种待测样品。通过DSC、XRD表征了处理前后样品熔点、晶型、结晶度和晶粒大小的变化,比较了两种处理方法对PGA特性粘度的影响,考察了非晶态PGA在六氟异丙醇中的稳定性。结果表明:急速冷却法得到非晶态PGA可以有效地避免PGA在DMSO中的热降解情况,有利于准确测量PGA分子量;非晶态PGA在六氟异丙醇中降解速度较快,测分子量时,应当现配现测。根据Mark-Houwink方程,拟合了重均相对分子量和特性粘度之间关系Ln(η)=-10.90*Ln(Mw)+0.96,线性相关系数r=0.995,可以利用该方程通过测量PGA的特性粘度值来估算其重均相对分子量。Based on the molecular determination methods of DMSO recrystallization and rapid cooling, two poly（glycolic acid） samples had been prepared. By the tests of DSC and XRD, the change of the crystal sizes and the degree of crystallinity of the samples were discussed, and the intrinsic viscosities of the different samples were measured and compared. The stability of the samples in hexafluoroisopropanol was also investigated. A series of results showed that the rapid cooling was effective to avoid the PGA＇s thermal degradation in DMSO; because the PGA degraded rapidly in HFIP solvent, the measurement of molecular weight should be carried out quickly after the PGA sample solvent was prepared. According to the Mark-Houwink equation, the relationship between the weight average molecular weight and intrinsic viscosity was built as. Ln（η）=- 10.90＊Ln（Mw）＋0. 96, r= 0. 995. The weight average molecular weight could be calculated by the determination of intrinsic viscosity due to this equation.

关 键 词：PGA DMSO重结晶 急速冷却 分子量 

分 类 号：R318.08[医药卫生—生物医学工程]