Characterization of biodegradable poly(3-hydroxybutyrate-co-butyleneadipate) copolymers obtained from their homopolymers by microwave-assisted transesterification
Characterization of biodegradable poly(3-hydroxybutyrate-co-butyleneadipate) copolymers obtained from their homopolymers by microwave-assisted transesterification
复制标题
DOI：
10.1016/j.polymer.2012.11.030
复制
发表时间：
2013-01-08
期刊：
影响因子：
4.6
通讯作者：
Scandola, Mariastella
中科院分区：
文献类型：
--
作者：
Impallomeni, Giuseppe;Carnemolla, Giovanni Marco;Scandola, Mariastella
以可生物降解的聚（R-3-羟基丁酸酯）（PH B）和聚（1，4-己二酸丁二醇酯）（PBA）为原料，在不同反应时间、原料组成和催化剂对甲苯磺酸用量的条件下，通过微波辅助酯交换反应合成了含（R）-3-羟基丁酸（HB）、1，4-丁二醇（B）和己二酸（A）的共聚物。通过凝胶渗透色谱法（GPC）、差示扫描量热法（DSC）、广角X射线衍射（WAXS）、H-1-NMR和C-13-NMR分别对共聚酯的分子量、热性能、摩尔组成和重复单元的平均嵌段长度进行了表征。根据实验条件，可以获得无规和微嵌段共聚物，重均分子量高达17，000。所有样品的玻璃化转变温度（Tg）都在PBA和PHB的Tg之间，而它们的结构从部分结晶到完全无定形。基质辅助激光解吸电离飞行时间（MALDI-TOF）质谱的共聚物，使我们能够确定，他们是羟基和羧基链端终止。(C)2012爱思唯尔有限公司保留所有权利。
Copolymers containing (R)-3-hydroxybutyric acid (HB), 1,4-butanediol (B), and adipic acid (A) were synthesized by microwave-assisted transesterification of biodegradable poly(R-3-hydroxybutyrate) (PHB) and poly(1,4-butyleneadipate) (PBA) in solution at different reaction times, composition of the starting mixture, and amount of 4-toluenesulfonic acid, used as a catalyst. The copolyesters were characterized with regard to their molecular weights, thermal properties, molar composition, and average block length of repeating units by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXS), H-1-NMR, and C-13-NMR, respectively. Random and microblock copolymers could be obtained depending on experimental conditions, with weight average molecular weight of up to 17,000. The glass transition temperature (Tg) of all samples lay in the range between the Tgs of PBA and PHB, while their structure varied from partially crystalline to totally amorphous. Matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectra of copolymers allowed us to ascertain that they were hydroxyl and carboxyl chain-end terminated. (C) 2012 Elsevier Ltd. All rights reserved.