LONG Zhizhong，ZHANG Liqiang，WU Qingding，TAN Zhili

(College of Mechanical and Electrical Engineering，Central South University of Forestry and Technology，Changsha 410004，China)

Abstract: According to the standard colorimetric system and surface powder extraction experiments, the variation of chemical composition and color of the surface of poplar powder compacts at different forming temperatures were studied. The experimental results show that: in the process of increasing the forming temperature, polysaccharides and hemicellulose are degraded at high temperatures and colored extracts are formed on the compaction surface to cause the color to darken. As the forming temperature increases, the color of the compaction surface becomes darker. When the forming temperature is in the range of 160～180 ℃, the overall color difference value increases and the brightness value decreases significantly. This range of forming temperature has a great impact on the color of compaction surface. The water content of powder of the compaction surface decreases with the increase of the forming temperature. Different extraction methods lead to large changes in the content of extracts. Under the same temperature conditions, the content of extracts obtained by 1% NaOH method is the highest, the content of the extracts obtained by hot water method is slightly more than that obtained by cold water method, and the content of the extracts obtained by benzyl alcohol method is the lowest.

Keywords: poplar powder; warm compaction; colored extract; chemical composition; color

收稿日期： 2019-12-05，修回日期：2020-01-15，在线出版时间：2020-04-03 17:04。

基金项目：湖南省自然科学基金项目，编号：2018JJ2681；湖南省教育厅科学研究重点项目，编号：19A512；湖南省工业领域重点研发计划项目，编号：2017GK2255；湖南省研究生科技创新项目，编号：CX20190628。

第一作者简介：龙治中(1996—)，男，硕士研究生，研究方向为机械制造及其自动化。E-mail：523444630@qq.com。

通信作者简介：张立强(1978—)，男，博士，副教授，硕士生导师，研究方向为木质粉末材料与金属材料成形。E-mail：21384881@qq.com。

文章编号：1008-5548(2020)03-0053-05

doi:10.13732/j.issn.1008-5548.2020.03.008

中图分类号：S781.6                              文献标志码：A