Accelerated weathering tests were conducted to evaluate the weathering resistance of poly(lactic acid) (PLA) based biocomposites without and with epoxidized natural rubber (ENR), that were reinforced with unmodified wood pulp fiber (WP) and silanized wood pulp fiber (modified WP). Changes in mechanical and thermal properties and morphology were observed, and structural and chemical degradation were analyzed. The addition of ENR improved the impact strength of the biocomposites before weathering, acting as an impact modifier. After the weathering test, the flexural properties of PLA-based biocomposite with ENR and silanized wood pulp fiber (ENR-modified WP) was better than the flexural properties of a biocomposite without ENR. The biodegradability of the biocomposites largely depended on the PLA matrix. The modified fibers have lower UV absorbance and can protect composites from UV light better than unmodified fibers. ENR and modified WP helped prevented the degradation of PLA. While weathering reduced the molecular weight of the WP and modified WP biocomposites by 78% and 61%, respectively, the molecular weight of the same biocomposites with ENR decreased by 51% and 50%, respectively. The accelerated weathering test produced cracks and increased surface roughness in the biocomposites and the glass transition temperature was reduced as a result of crystallization and chain shortening. These indicated that the biocomposite based containing ENR and silanized wood pulp fiber had better weathering resistance due to lowest absorption of UV radiation which was more suitable for applications in construction, furniture, and exterior and interior decoration.

进行了加速老化试验以评估不含和含有环氧化天然橡胶 (ENR) 的聚乳酸 (PLA) 基生物复合材料的耐候性，这些生物复合材料用未改性木浆纤维 (WP) 和硅烷化木浆纤维 (改性 WP) 增强). 观察了机械和热性能以及形态的变化，并分析了结构和化学降解。ENR 的添加提高了生物复合材料在风化前的冲击强度，起到了冲击改性剂的作用。耐候性测试后，含 ENR 和硅烷化木浆纤维（ENR 改性 WP）的 PLA 基生物复合材料的弯曲性能优于不含 ENR 的生物复合材料的弯曲性能。生物复合材料的生物降解性在很大程度上取决于 PLA 基质。改性纤维具有较低的紫外线吸收率，比未改性纤维能更好地保护复合材料免受紫外线照射。ENR 和改良的 WP 有助于防止 PLA 的降解。虽然风化使 WP 和改性 WP 生物复合材料的分子量分别降低了 78% 和 61%，但具有 ENR 的相同生物复合材料的分子量分别降低了 51% 和 50%。加速老化试验在生物复合材料中产生裂纹并增加表面粗糙度，并且玻璃化转变温度由于结晶和链缩短而降低。这些表明含有 ENR 和硅烷化木浆纤维的生物复合材料由于对紫外线辐射的吸收最低而具有更好的耐候性，更适合建筑、家具、