Textile Institute, Sichuan University, Chengdu 610065, China.
Textile Institute, Sichuan University, Chengdu 610065, China.
Int J Biol Macromol. 2019 Sep 1;136:1069-1075. doi: 10.1016/j.ijbiomac.2019.06.141. Epub 2019 Jun 20.
Super-tough poly (l-lactide) (PLLA) without compromising its biodegradability and biocompatibility was fabricated by reactive blending with PLLA and maleic anhydride grafted starch (MS)/poly (ethylene glycol) diacrylate (PEGDA). PEGDA as reactive compatibilizer exhibits higher compatibilization efficiency and significant plasticization effect in PLLA matrix. Fourier transform infrared spectroscopy (FT-IR) confirmed that PEGDA monomer successfully located at the molecules of MS and some interesterification reactions occurred between PEGDA and PLLA. The ductility of PLLA materials were significantly improved, for example, the elongation of break increased to 298% at the optimum PLLA/MS/PEGDA content. Dynamic mechanical thermal analysis (DMTA) demonstrated the glass transition temperature of blends decreased with the contents of MS/PEGDA increasing. The differential scanning calorimeter (DSC) results revealed that cold crystallization temperature and melting temperature of blends were decreased with the augment of the contents of MS/PEGDA. Wide angle X-ray diffraction (WARD) and DSC certified that a high crystalline article was obtained through practical extrusion process, which could propagate shear yielding deformation to dissipate energy during tensile fracture. Scanning electron microscope (SEM) demonstrated that the blends with PEGDA did not exhibit a visible phase-separated morphology from cryogenic fractured surfaces compared with the blend without PEGDA.
通过与 PLLA 和马来酸酐接枝淀粉（MS）/聚乙二醇二丙烯酸酯（PEGDA）的反应共混，制备了兼具生物降解性和生物相容性的超韧聚（L-丙交酯）（PLLA）。作为反应性增容剂的 PEGDA 在 PLLA 基体中表现出更高的增容效率和显著的增塑效应。傅里叶变换红外光谱（FT-IR）证实 PEGDA 单体成功定位在 MS 的分子上，并且 PEGDA 和 PLLA 之间发生了一些酯交换反应。PLLA 材料的延展性得到了显著提高，例如，断裂伸长率在最佳 PLLA/MS/PEGDA 含量下增加到 298%。动态力学热分析（DMTA）表明共混物的玻璃化转变温度随 MS/PEGDA 含量的增加而降低。差示扫描量热法（DSC）结果表明，共混物的冷结晶温度和熔融温度随 MS/PEGDA 含量的增加而降低。广角 X 射线衍射（WARD）和 DSC 证明，通过实际的挤出工艺可以获得高结晶度的制品，该制品可以在拉伸断裂过程中通过传播剪切屈服变形来耗散能量。扫描电子显微镜（SEM）表明，与不含 PEGDA 的共混物相比，具有 PEGDA 的共混物在从低温断裂表面观察时没有表现出明显的相分离形态。
