Wang Qiuyi, Wu Xinwu, Yuan Chenglong, Lou Zhichao, Li Yanjun
College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China.
Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing 210037, China.
Molecules. 2020 Apr 24;25(8):1999. doi: 10.3390/molecules25081999.
The aim of this study was to investigate the effects of the heat treatment time and initial moisture content of bamboo on the corresponding chemical composition, crystallinity, and mechanical properties after saturated steam heat treatment at 180 °C. The mechanism of saturated steam heat treatment of bamboo was revealed on the micro-level, providing a theoretical basis for the regulation of bamboo properties and the optimization of heat treatment process parameters. XRD patterns of the treated bamboo slices were basically the same. With the increase in the initial moisture content of bamboo, the crystallinity of bamboo increased first and then decreased after treatment. Due to the saturated steam heat treatment, the content of cellulose and lignin in bamboo slices increased while the content of hemicellulose decreased, but the content of cellulose in bamboo with a 40% initial moisture content increased first and then decreased. The shear strength of treated bamboo changed little within 10 min after saturated steam heat treatment, and then decreased rapidly. During the first 20 min with saturated steam heat treatment, the compressive strength, flexural strength, and flexural modulus of elasticity of the treated bamboo increased, and then decreased.
本研究旨在探究竹子的热处理时间和初始含水率对其在180℃饱和蒸汽热处理后的化学成分、结晶度及力学性能的影响。从微观层面揭示了竹子饱和蒸汽热处理的机理,为竹子性能调控及热处理工艺参数优化提供理论依据。处理后竹片的XRD图谱基本相同。随着竹子初始含水率的增加,处理后竹子的结晶度先升高后降低。由于饱和蒸汽热处理,竹片中纤维素和木质素含量增加,半纤维素含量降低,但初始含水率为40%的竹子中纤维素含量先升高后降低。饱和蒸汽热处理10分钟内,处理后竹子的剪切强度变化不大,之后迅速下降。在饱和蒸汽热处理的前20分钟内,处理后竹子的抗压强度、抗弯强度和抗弯弹性模量升高,之后下降。