Xu Jiayu, Zhou Zhezhe, Zhang Xiaochun, Xu Yantao
College of Chemistry and Materials Engineering, Zhejiang A & F University, Hangzhou 311300, China.
Zhejiang Provincial Collaborative Innovation Center for Bamboo Resources and High-Efficiency Utilization, Hangzhou 311300, China.
Polymers (Basel). 2023 Oct 20;15(20):4162. doi: 10.3390/polym15204162.
Given the increasingly prominent contradiction between the supply of and demand for wood, the abundant resource of bamboo can be a good substitute. Bamboo scrimber can effectively improve the utilization rate of bamboo and has good mechanical properties. However, bamboo scrimber has the problem of poor mildew resistance, and does not meet the requirements for outdoor applications. In this study, in order to further improve the mildew resistance and mechanical properties of bamboo scrimber, alkali treatment was used to remove some nutrients from the bamboo bundles and change the pH of the bamboo scrimber. The results showed that nutrients such as hemicellulose, lignin, starch, and sugar were notably removed from bamboo bundles, and the pH of bamboo was slightly alkaline. The anti-mildew effect was significantly enhanced, which could allow use in outdoor environments, and the mechanical properties and dimensional stability were also improved. Among them, TB6 bamboo scrimber showed comprehensively excellent properties. The infection time in the laboratory mildew test increased from 3 days to more than 30 days, and the infection time in the outdoor mildew resistance test increased from 1 week to more than 8 weeks; the static bending intensity of TB6 increased by 62.6% to 150 MPa, and the bending modulus increased by 71.7% to 14.2 GPa; the change rate of water absorption thickness was reduced to 0.58%. This modification method effectively improved the mildew resistance of bamboo scrimber, while maintaining high mechanical strength, and provides a new method for the outdoor application of bamboo scrimber.
鉴于木材供需矛盾日益突出,丰富的竹资源可成为良好的替代品。竹集成材能有效提高竹子利用率且具有良好的力学性能。然而,竹集成材存在防霉性能差的问题,不符合户外应用要求。本研究中,为进一步提高竹集成材的防霉性能和力学性能,采用碱处理去除竹束中的一些营养成分并改变竹集成材的pH值。结果表明,竹束中的半纤维素、木质素、淀粉和糖等营养成分显著去除,竹材pH值呈微碱性。防霉效果显著增强,可用于户外环境,力学性能和尺寸稳定性也得到改善。其中,TB6竹集成材表现出综合优异性能。实验室防霉试验中的感染时间从3天增加到30多天,户外防霉试验中的感染时间从1周增加到8周以上;TB6的静曲强度提高62.6%至150MPa,弯曲模量提高71.7%至14.2GPa;吸水厚度变化率降至0.58%。这种改性方法有效提高了竹集成材的防霉性能,同时保持了较高的机械强度,为竹集成材的户外应用提供了一种新方法。