文献类型：期刊文献

中文题名：基于纤维素骨架的毛竹热处理材力学性能研究

英文题名：Research on mechanical properties of Phyllostachys edulis heat treatment materials based on cellulose skeleton

作者：王雪苑[1,2] 黄宇翔[2] 马尔妮[1]

第一作者：王雪苑

机构：[1]北京林业大学材料科学与技术学院,北京100083;[2]中国林业科学研究院木材工业研究所,北京100091

年份：2023

卷号：45

期号：7

起止页码：130-138

中文期刊名：北京林业大学学报

外文期刊名：Journal of Beijing Forestry University

收录：CSTPCD;;北大核心:【北大核心2020】；CSCD:【CSCD2023_2024】；

基金：国家自然科学基金项目(32001380)。

语种：中文

中文关键词：毛竹;纤维素骨架;热处理;力学性能;微观结构

外文关键词：Phyllostachys edulis;cellulose skeleton;heat treatment;mechanical property;microstructure

分类号：S781.9;S781.7

摘要：【目的】分析热处理过程中毛竹主要承载细胞-纤维细胞其细胞壁骨架物质纤维素微观结构与其微力学性能的变化,以期从纤维细胞构效关系的角度解释热处理毛竹宏观力学性能的变化。【方法】以4年生毛竹为实验材料,以酸性亚氯酸钠溶液和氢氧化钠溶液脱除毛竹细胞壁基质,得到仅保留纤维素的毛竹纤维细胞。对未处理的毛竹试件和毛竹纤维细胞进行饱和蒸汽热处理,处理时间8 h,温度140和200℃。之后分别测定毛竹试件的物理力学性质(密度、抗弯、抗拉性能)和纤维细胞的单根纤维拉伸性能、细胞壁硬度和弹性模量等微力学性能。利用扫描电子显微镜、X射线衍射技术、傅里叶变换红外光谱分析和聚合度测定表征热处理前后毛竹纤维素形态以及微观结构的变化。【结果】毛竹的密度、顺纹抗弯和抗拉性能均随热处理温度的上升而下降。140℃热处理对毛竹纤维细胞的拉伸强度和弹性模量影响不显著,但热处理温度提高至200℃后,纤维细胞的抗拉强度急剧下降,由未热处理的808.30 MPa减少至479.23 MPa。此外,随着热处理温度的上升,纤维细胞的细胞壁硬度增加。热处理后仅保留纤维素的毛竹纤维细胞微观形貌基本不变,纤维素的结晶度增加,分子间氢键增加,聚合度下降。【结论】热处理会降低毛竹的密度、顺纹抗弯和抗拉性能,并降低了仅保留纤维素的毛竹纤维细胞的拉伸强度,但会在一定程度上改变纤维细胞壁的微力学性能。这与热处理后毛竹纤维素的结晶度、氢键体系和聚合度的变化密切相关。
[Objective]This paper aims to analyze the changes of microstructure and micromechanical properties of fiber cell,the main carrier cell of moso bamboo in the process of heat treatment,in order to explain the changes of macromechanical properties of moso bamboo from the perspective of structuralactivity relationship among fiber cells.[Method]The cell wall matrix of four-year-old moso bamboo was removed with acid sodium chlorite solution and sodium hydroxide solution to obtain fiber cells with only cellulose.The untreated bamboo and bamboo fiber cells were subjected to saturated steam heat treatment at 140 and 200℃for 8 h.Then,the physical and mechanical properties(density,flexural and tensile properties)and the micromechanical properties of fiber cells,such as single fiber tensile properties,cell wall hardness and elastic modulus,were measured.Scanning electron microscopy,X-ray diffraction,Fourier transform infrared spectroscopy and polymerization degree were used to characterize the changes in morphology and microstructure of cellulose before and after heat treatment.[Result]The density,bending and tensile properties of moso bamboo decreased with the increase of heat treatment temperature.The tensile strength and elastic modulus of fiber cells were not significantly affected by heat treatment at 140℃,but the tensile strength of fiber cells decreased sharply when the heat treatment temperature was increased to 200℃,from 808.30 MPa without heat treatment to 479.23 MPa.In addition,with the increase of heat treatment temperature,the hardness of fiber cell wall increased.After heat treatment,the micromorphology of fiber cells with only cellulose remained basically unchanged,and the crystallinity of cellulose increased,intermolecular hydrogen bond increased,and polymerization degree decreased.[Conclusion]Heat treatment can reduce the density,bending and tensile properties of moso bamboo,and reduce the tensile strength of moso bamboo fiber cells with only cellulose,but can change the micromechanical properties of fiber cell wall to a certain extent.This is closely related to the change of crystallinity,hydrogen bond system and polymerization degree of cellulose after heat treatment.