文献类型：期刊文献

中文题名：真空热处理对落叶松木材纤维素形貌及结构的影响

英文题名：Effects of Vacuum Heat Treatment on Morphology and Structure of Larch Wood Cellulose

作者：孙柏玲[1] 王小青[1] 柴宇博[1]

第一作者：孙柏玲

机构：[1]中国林业科学研究院木材工业研究所,北京100091

年份：2024

卷号：44

期号：7

起止页码：1928-1933

中文期刊名：光谱学与光谱分析

外文期刊名：Spectroscopy and Spectral Analysis

收录：CSTPCD;;Scopus;北大核心:【北大核心2023】；CSCD:【CSCD2023_2024】；PubMed;

基金：国家自然科学基金项目(31901244)资助。

语种：中文

中文关键词：真空热处理;落叶松;纤维素;形貌;结构

外文关键词：Vacuum heat treatment;Laria kaempferi;Cellulose;Morphology;Structure

分类号：O657.33

摘要：以我国东北主要用材树种落叶松木材为研究对象,采用真空热处理方法对其材质进行改良,探究其纤维素形貌及结构热响应机制。采用湿化学法提取未处理和不同真空热处理条件下(180~220℃温度范围,处理6 h)落叶松木材纤维素,利用扫描电子显微镜观察其形貌,X射线光电子能谱和X射线衍射仪分析其化学结构及结晶度变化。结果表明:未处理木材提取的纤维素呈棒状且表面有序平行结构,热处理后木材纤维素变弯曲且表面呈扭曲结构,并随热处理温度升高,纤维素表面扭曲越显著。由X射线光电子能谱分析,随热处理强度增加,纤维素O/C比值由未处理材65.5%降低至59.5%,并且C1含量增加、C2和C3分别降低,表明热处理木材提取的纤维素碳链缩短,并且其表面存在半纤维素以及热处理过程中木质素与碳水化合物缩聚反应形成的木质素-碳水化合物。随热处理温度提高,纤维素结晶度增加,同时纤维素中Ⅱ型占比提高、Ⅰ型降低,并且二者晶胞结构和分子基团构象存在差异,进而导致热处理前后木材提取的纤维素形貌结构不同。研究结果有助于深入理解木材化学成分热响应特性,为优化真空热处理改性木材工艺提供理论依据。
In this study,larch wood,the main timber species in Northeast China,was improved by vacuum heat treatment to explore its cellulose morphology and structural thermal response mechanism.The wet chemical method was used to extract the cellulose of untreated and heat-treated larch wood under different vacuum heat treatment conditions(180~220℃,6 hours).The cellulose morphology was observed by scanning electron microscope,and its chemical structure and crystallinity were analyzed by X-ray photoelectron spectroscopy and X-ray diffraction.The results showed that the cellulose extracted from untreated wood was rod-shaped and had an ordered parallel and rigid structure.After heat treatment,the wood cellulose curved,and its surface twisted.With the increase inheat treatment temperature,the surface distortion of cellulose became more significant.The X-ray photoelectron spectroscopy analysis showed that the increase in heat treatment intensity decreased the cellulose O/C ratio from 65.5% to 59.5%.The C1 content increased,and C2 and C3 decreased,respectively,indicating that the cellulose carbon chain extracted from heat-treated wood was shortened.Hemicellulose and lignin-carbohydrate formed by the condensation reaction of lignin and carbohydrate during heat treatment might remain on its surface.In addition,with the increase inheat treatment temperature,wood cellulose's crystallinity increased,the proportion of celluloseⅡincreased,and celluloseⅠdecreased.Furthermore,the morphology of cellulose extracted from wood before and after heat treatment presented different structures due to the differences in the cell structure and molecular group conformation between celluloseⅠandⅡ.This research will help to deeply understand the thermal response characteristics of wood chemical composition and provide a theoretical basis for the optimization of wood vacuum heat treatment technology.