Papadopoulou Katerina, Klonos Panagiotis A, Kyritsis Apostolos, Mašek Ondřej, Wurzer Christian, Tsachouridis Konstantinos, Anastasiou Antonios D, Bikiaris Dimitrios N
Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
Department of Physics, Zografou Campus, National Technical University of Athens, 15780 Athens, Greece.
Polymers (Basel). 2023 Feb 20;15(4):1049. doi: 10.3390/polym15041049.
Biodegradable polymers offer a promising alternative to the global plastic problems and especially in the last decade, to the microplastics problems. For the first time, samples of poly(butylene succinate) (PBSu) biocomposites containing 1, 2.5, and 5 wt% biochar (BC) were prepared by in situ polymerization via the two-stage melt polycondensation procedure. BC was used as a filler for the PBSu to improve its mechanical properties, thermal transitions, and biodegradability. The structure of the synthesized polymers was examined by H and C nuclear magnetic resonance (NMR) and X-Ray diffraction (XRD) along with an estimation of the molecular weights, while differential scanning calorimetry (DSC) and light flash analysis (LFA) were also employed to record the thermal transitions and evaluate the thermal conductivity, respectively. It was found that the amount of BC does not affect the molecular weight of PBSu biocomposites. The fine dispersion of BC, as well as the increase in BC content in the polymeric matrix, significantly improves the tensile and impact strengths. The DSC analysis results showed that BC facilitates the crystallization of PBSu biocomposites. Due to the latter, a mild and systematic increase in thermal diffusivity and conductivity was recorded indicating that BC is a conductive material. The molecular mobility of PBSu, local and segmental, does not change significantly in the biocomposites, whereas the BC seems to cause an increase in the overall dielectric permittivity. Finally, it was found that the enzymatic hydrolysis degradation rate of biocomposites increased with the increasing BC content.
可生物降解聚合物为全球塑料问题，尤其是过去十年中的微塑料问题提供了一种有前景的解决方案。首次通过两步熔融缩聚原位聚合法制备了含有1 wt%、2.5 wt%和5 wt%生物炭（BC）的聚丁二酸丁二醇酯（PBSu）生物复合材料样品。BC用作PBSu的填料，以改善其机械性能、热转变性能和生物降解性。通过氢和碳核磁共振（NMR）、X射线衍射（XRD）对合成聚合物的结构进行了研究，并对分子量进行了估算，同时还采用差示扫描量热法（DSC）和光闪分析法（LFA）分别记录热转变和评估热导率。结果发现，BC的用量不影响PBSu生物复合材料的分子量。BC的良好分散以及聚合物基体中BC含量的增加，显著提高了拉伸强度和冲击强度。DSC分析结果表明，BC促进了PBSu生物复合材料的结晶。由于后者，记录到热扩散率和热导率有温和且系统的增加，表明BC是一种导电材料。在生物复合材料中，PBSu的局部和链段分子迁移率没有显著变化，而BC似乎导致了整体介电常数的增加。最后，发现生物复合材料的酶水解降解率随BC含量的增加而提高。
