Svarcova Anna, Dvorackova Marie, Svoboda Petr
Department of Polymer Engineering, Faculty of Technology, Tomas Bata University in Zlin, Vavreckova 5669, 76001 Zlin, Czech Republic.
Department of Environmental Protection Engineering, Faculty of Technology, Tomas Bata University in Zlin, Nad Ovcirnou 3685, 76001 Zlin, Czech Republic.
Molecules. 2025 May 22;30(11):2252. doi: 10.3390/molecules30112252.
This study investigates the impact of hydrolysis on the crystallization behavior of poly(butylene succinate-co-adipate) (PBSA), a biodegradable polyester. Hydrolysis was conducted in a controlled environment using phosphate-buffered saline at 70 °C to isolate the impact of hydrolytic degradation on the polymer's properties. The consequent changes in molecular weight characteristics were tracked using gel permeation chromatography (GPC), revealing a decrease in both weight average molecular weight (M) and an increase in polydispersity index (PDI) as hydrolysis progressed. The thermal behavior of PBSA during hydrolysis was thoroughly investigated using differential scanning calorimetry (DSC), which demonstrated significant changes in melting temperature (T), glass transition temperature (T), and crystallinity (X). These changes in T and T suggest a change in copolymer composition, likely due to the greater susceptibility of the adipic acid unit to hydrolysis compared to the succinic acid unit. Furthermore, polarized optical microscopy (POM) was employed to observe the morphological evolution of PBSA, showing a transition from spherulitic structures in the early stages of hydrolysis to dendritic structures with prolonged hydrolysis time. The decrease in nucleation activity led to a reduction in the number of spherulites, which in turn allowed the remaining spherulites to grow larger.
本研究考察了水解对聚（丁二酸丁二醇酯 - 共 - 己二酸丁二醇酯）（PBSA）（一种可生物降解聚酯）结晶行为的影响。在70°C的磷酸盐缓冲盐溶液中于可控环境下进行水解，以分离水解降解对聚合物性能的影响。使用凝胶渗透色谱法（GPC）追踪水解过程中分子量特征的相应变化，结果显示随着水解的进行，重均分子量（M）下降，多分散指数（PDI）增加。使用差示扫描量热法（DSC）对水解过程中PBSA的热行为进行了全面研究，结果表明其熔点（T）、玻璃化转变温度（T）和结晶度（X）发生了显著变化。T和T的这些变化表明共聚物组成发生了变化，这可能是由于己二酸单元比琥珀酸单元更容易发生水解。此外，采用偏光显微镜（POM）观察PBSA的形态演变，结果显示在水解初期从球晶结构转变为随着水解时间延长而出现的树枝状结构。成核活性的降低导致球晶数量减少，进而使剩余的球晶生长得更大。
