Biodegradation rates and mechanical properties of poly(3-hydroxybutyrate) (PHB) composites with green algae and cyanobacteria were investigated for the first time. To the authors knowledge, the addition of microbial biomass led to the biggest observed effect on biodegradation so far. The composites with microbial biomass showed an acceleration of the biodegradation rate and a higher cumulative biodegradation within 132 days compared to PHB or the biomass alone. In order to determine the causes for the faster biodegradation, the molecular weight, the crystallinity, the water uptake, the microbial biomass composition and scanning electron microscope images were assessed. The molecular weight of the PHB in the composites was lower than that of pure PHB while the crystallinity and microbial biomass composition were the same for all samples. A direct correlation of water uptake and crystallinity with biodegradation rate could not be observed. While the degradation of molecular weight of PHB during sample preparation contributed to the improvement of biodegradation, the main reason was attributed to biostimulation by the added biomass. The resulting enhancement of the biodegradation rate appears to be unique in the field of polymer biodegradation. The tensile strength was lowered, elongation at break remained constant and Young’s modulus was increased compared to pure PHB.

首次研究了聚（3-羟基丁酸酯）（PHB）与绿藻和蓝藻复合材料的生物降解速率和机械性能。据作者所知，迄今为止，微生物生物质的添加对生物降解产生了最大的观察到的影响。与单独的 PHB 或生物质相比，含有微生物生物质的复合材料显示出生物降解速率加快，并且在 132 天内具有更高的累积生物降解量。为了确定生物降解速度加快的原因，对分子量、结晶度、吸水率、微生物生物质组成和扫描电子显微镜图像进行了评估。复合材料中 PHB 的分子量低于纯 PHB，而所有样品的结晶度和微生物量组成均相同。无法观察到吸水率和结晶度与生物降解率的直接相关性。虽然样品制备过程中PHB分子量的降低有助于生物降解性的改善，但主要原因是添加的生物质的生物刺激。由此产生的生物降解速率的提高在聚合物生物降解领域似乎是独一无二的。与纯 PHB 相比，拉伸强度降低，断裂伸长率保持恒定，杨氏模量增加。由此产生的生物降解速率的提高在聚合物生物降解领域似乎是独一无二的。与纯 PHB 相比，拉伸强度降低，断裂伸长率保持恒定，杨氏模量增加。由此产生的生物降解速率的提高在聚合物生物降解领域似乎是独一无二的。与纯 PHB 相比，拉伸强度降低，断裂伸长率保持恒定，杨氏模量增加。