Tang Tong, Fang Changhua, Sui Zhen, Fu Chuanle, Li Xuelin
School of Art & Design, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China.
Key Laboratory of Bamboo and Rattan Science and Technology of the State Forestry Administration, Department of Biomaterials, International Center for Bamboo and Rattan, Beijing 100102, China.
Polymers (Basel). 2025 Mar 12;17(6):747. doi: 10.3390/polym17060747.
Green, newly felled bamboo stems are prone to cracking during the drying process due to the growth stress and moisture gradient. To improve the drying quality and dimensional stability of bamboo stems, this study applied hygrothermal treatment under atmospheric pressure to newly felled bamboo stems. The temperature, relative humidity, and duration of the treatment were optimized using an orthogonal L (3) experimental design. The results show that the surface color of round bamboo became more uniform after hygrothermal treatment. Furthermore, hygrothermal treatment could reduce the cuticular wax and silicon layer detachment on the surface of round bamboo after drying. According to the range and variance analysis, the relative humidity had the greatest impact on dimensional stability, followed by treatment duration, whereas the temperature had a limited effect. The swelling rate of round bamboo under a hygrothermal treatment at a relative humidity of 95%, a temperature of 95 °C, and a duration of 3 h was decreased 53.72% and 62.76% compared with untreated round bamboo after moisture or water absorption for 7 d, respectively. However, no significant difference was observed in the color of the round bamboo under different hygrothermal treatment conditions. Overall, this study suggests that hygrothermal treatment could be a highly promising technology for improving the dimensional stability of newly felled bamboo stems.
新鲜砍伐的绿色竹茎在干燥过程中，由于生长应力和水分梯度，容易出现开裂现象。为了提高竹茎的干燥质量和尺寸稳定性，本研究对新鲜砍伐的竹茎进行了常压湿热处理。采用正交L(3)实验设计对处理的温度、相对湿度和持续时间进行了优化。结果表明，圆竹经湿热处理后表面颜色变得更加均匀。此外，湿热处理可以减少干燥后圆竹表面的角质蜡和硅层脱落。根据极差和方差分析，相对湿度对尺寸稳定性的影响最大，其次是处理持续时间，而温度的影响有限。与未经处理的圆竹在吸湿或吸水7 d后相比，在相对湿度95%、温度95℃、持续时间3 h的湿热处理条件下，圆竹的膨胀率分别降低了53.72%和62.76%。然而，在不同的湿热处理条件下，圆竹的颜色没有显著差异。总体而言，本研究表明湿热处理可能是一种极具前景的提高新鲜砍伐竹茎尺寸稳定性的技术。
