竹龄和竹秆纵向部位对青皮竹物理力学性能的影响  

Effects of age and culm longitudinal position on physical and mechanical properties of Bambusa textilis McClure bamboo

作　　者：姚开泰 谭伟 周海洋 郝笑龙 许黎明 王清文 欧荣贤 YAO Kaitai;TAN Wei;ZHOU Haiyang;HAO Xiaolong;XU Liming;WANG Qingwen;OU Rongxian(Key Laboratory for Biobased Materials and Energy of Ministry of Education,College ofMaterials and Energy,South China Agricultural University,Guangzhou 510642,China;Guangdong Haipeng Bamboo Fiber New Material Technology Co.Ltd.,Zhaoqing 526300,Guangdong,China)

机构地区：[1]华南农业大学材料与能源学院生物基材料与能源教育部重点实验室,广州510642 [2]广东海鹏竹纤维新材料科技有限公司,广东肇庆526300

出　　处：《林业工程学报》2021年第5期76-81,共6页Journal of Forestry Engineering

基　　金：国家重点研发计划(2019YFD1101202);国家自然科学基金(32071698,31870547);广东省重点领域研发计划项目(2020B0202010008)。

摘　　要：广东省广宁县拥有丰富的青皮竹资源,但因其径小壁薄而缺乏合理的开发利用。以青皮竹为研究对象,探究竹龄(1~5年生)和竹秆纵向部位(1~8 m)对竹材密度、纤维形态、化学成分、结晶度和纤维束拉伸性能的影响规律,以期为青皮竹的合理采伐利用和高性能竹纤维基复合材料开发提供依据。结果显示:随竹龄增大,青皮竹的密度逐渐增大,4年生密度达到最大值0.83 g/cm 3,纤维素含量由46%降低至40%,抽提物含量由9.1%提高至17.6%,相对结晶度(CrI)略有降低,但纤维形态无明显差异,纤维束拉伸性能提高,4年生拉伸强度达到最大值683.4 MPa,5年生拉伸模量达到最大值36.5 GPa。随竹秆部位升高,青皮竹密度、化学成分和相对结晶度变化较小,但随着竹秆部位升高,纤维趋于细短,纤维束拉伸性能变差,拉伸强度从离地1~2 m处的683.4 MPa降低至7~8 m处的549.1 MPa。因生长发育期受寒潮雨雪冰冻天气影响,3年生青皮竹的密度、纤维形态、纤维素和抽提物含量变异较大。Guangning County in Guangdong Province,China,has abundant Bambusa textilis McClure(BTM)bamboo resources,but it does not reasonably develop and utilize BTM due to its small diameter and thin wall,and therefore there are limited reports on physical-mechanical properties of BTM in scientific literature.In this study,with a view to provide a basis for the rational harvesting and utilization of BTM and developing high-performance bamboo fiber-based composites,the oven-dried density,fiber morphology,chemical composition,crystallinity,and tensile properties of fiber bundle of BTM from 1-to 5-year-old culms and located at different culm longitudinal positions(1-8 m above the ground)were investigated.Results showed that,with the increasing bamboo age,the oven-dried density of BTM increased gradually and reached a maximum value of 0.83 g/cm 3 at 4-year-old.The cellulose content of BTM decreased from 46%to 40%with the increasing age,and the extract content increased from 9.1%to 17.6%.The relative crystallinity(CrI)of BTM decreased slightly while no obvious differences were observed in fiber morphology with the increasing age due to the limitation of fiber cell size after reaching the full culm height.The tensile properties of the fiber bundles increased with age,which was caused by the thickening of fiber cell walls.The 4-year-old fiber bundles exhibited the maximum tensile strength of 683.4 MPa and the 5-year-old ones reached the maximum tensile modulus of 36.5 GPa.The oven-dried density,chemical composition,and CrI of BTM changed slightly along the culm position.The fiber length,fiber width,and tensile properties of fiber bundles decreased with the increase of the culm position.The tensile strength of fiber bundles decreased from 683.4 MPa at 1-2 m above the ground to 549.1 MPa at 7-8 m,which may be related to the shorter fiber morphology in higher culm position.The 3-year-old BTM exhibited abnormal variation in density,fiber morphology,cellulose,and extract content,which could be due to the cryogenic freezing rain and sn

关 键 词：青皮竹 纤维束 化学成分 纤维形态 拉伸性能 结晶度 

分 类 号：S781.9[农业科学—木材科学与技术]