热处理对竹基纤维复合材料性能的影响

Effect of Thermal Treatment on the Properties of Bamboo-Based Fiber Composites

毛竹竹材的纤维化单板经高温处理后,热压制备成竹基纤维复合材料(BFC)。分析热处理对纤维化竹单板化学性能的影响及热处理对BFC表面颜色、尺寸稳定性、力学性能的影响。结果表明:纤维化竹单板经热处理后,其综纤维素和α-纤维素的含量相对于未处理材显著降低,其中半纤维素含量降幅最大;热处理后竹材的pH值相对于未处理材显著降低,碱缓冲容量显著增大,而酸缓冲容量降低。由纤维化竹单板经热处理后制备的BFC,表面颜色变深,吸水厚度膨胀率和吸水宽度膨胀率相对于未处理材显著降低,尺寸稳定性得到改善;材料的静曲强度和水平剪切强度相对于未处理材显著降低,且随着蒸汽压力的增大和热处理时间的增长呈逐渐降低的趋势,而弹性模量变化不显著。

The Phyllostachys edulis bamboo fibrous veneers were heat-treated at high temperatures, and then made for BFC （bamboo-based fiber composites）. The chemical properties of bamboo fibrous veneers were measured, and surface color, dimensional stability, mechanical properties of BFC were studied. The results pointed-out that chemical degradation occurred, the contents of holocellulose and α-cellulose decreased significantly, mainly in relation to hemicelluloses contents. pH value decreased after thermal treatment, whereas, alkali buffering capacity increased compared with control samples and acid buffering capacity decreased. Thermal treatment can significantly change the surface color of BFC, and the board surface was darkened. The dimensional stability of BFC was significantly improved by reducing thickness swelling and wideness swelling. The mechanical properties were affected with the reduction in MOR （modulus of rupture） and HS （horizontal shear strength） which decreased with increased steam pressure and treatment duration, but MOE （modulus of elasticity） was affected slightly.