Jiang Huan, Wang Ge, Chen Fuming, Deng Jianchao, Chen Xiaoyi
Department of Biomaterials, International Centre for Bamboo and Rattan, Beijing 100102, China.
Key Laboratory of National Forestry and Grassland Administration/Beijing for Bamboo & Rattan Science and Technology, Beijing 100102, China.
Polymers (Basel). 2022 Oct 8;14(19):4220. doi: 10.3390/polym14194220.
This study aimed to investigate the mechanical property decay that might occur during actual use and soil burial degradation of bamboo fiber lunch boxes. For this, the effects of three accelerated aging methods, namely damp-heat treatment, freeze-thaw cycle, and artificial weathering cycle, on the tensile strength, dynamic viscoelasticity, and chemical composition of bamboo fiber lunch boxes were compared, and a correlation of their mechanical property decay with soil burial degradation was established to obtain an acceleration factor (SAF) with aging time as a reference. The results showed that the mechanical properties of the bamboo fiber lunch box decreased to different degrees under the three accelerated methods, and the tensile strength decreased to less than 50% after 36 h of damp-heat treatment, 5 freeze-thaw cycles, and 11 artificial weathering cycles. However, after 10 days, the mechanical property of lunch box in soil degradation decreased by more than 50%. Infrared spectroscopy demonstrated rapid hemicellulose degradation during damp-heat treatment and freeze-thaw cycle, as well as a minor quantity of lignin, and a significant amount of lignin under artificial weathering cycle. With the freeze-thaw cycle and the artificial weathering cycle, the relative crystallinity dropped quickly, by 32.3% and 21.5%, respectively, but under damp-heat treatment, the crystallinity dropped barely, by 43.5%. The damage caused by the freeze-thaw cycle to the mechanical properties of bamboo fiber lunch boxes was greater than that by the damp-heat treatment and artificial weathering cycle. The fluctuation of SAF under freeze-thaw cycle was also more drastic. Compared to the artificial weathering cycle, the damp-heat treatment was more stable and reliable in predicting the decay law of soil burial degradation tensile strength of bamboo fiber lunch boxes.
本研究旨在探究竹纤维饭盒在实际使用和土壤掩埋降解过程中可能发生的力学性能衰减。为此，比较了湿热处理、冻融循环和人工气候循环这三种加速老化方法对竹纤维饭盒拉伸强度、动态粘弹性和化学成分的影响，并建立了它们的力学性能衰减与土壤掩埋降解之间的相关性，以获得以老化时间为参考的加速因子（SAF）。结果表明，在三种加速方法下，竹纤维饭盒的力学性能均有不同程度下降，湿热处理36小时、5次冻融循环和11次人工气候循环后，拉伸强度降至50%以下。然而，10天后，饭盒在土壤降解中的力学性能下降超过50%。红外光谱表明，在湿热处理和冻融循环过程中半纤维素迅速降解，同时有少量木质素，而在人工气候循环下有大量木质素。随着冻融循环和人工气候循环，相对结晶度迅速下降，分别下降了32.3%和21.5%，但在湿热处理下，结晶度仅下降了4.5%。冻融循环对竹纤维饭盒力学性能造成的损伤大于湿热处理和人工气候循环。冻融循环下SAF的波动也更为剧烈。与人工气候循环相比，湿热处理在预测竹纤维饭盒土壤掩埋降解拉伸强度的衰减规律方面更稳定可靠。
