Study On Fabrication And Properties Of Wood Ceramics From Tension Wood Templates

In order to solve the problem of low utilization rate such as sawing and cracking in the processing and utilization of poplar tension wood,this study selected poplar tension wood as the wood material for making wood ceramics.The phenolic resin was combined with tension wood by vacuum impregnation,and the precursor of wood ceramics was carbonized in a high-temperature environment to prepare wood ceramics.The different phenolic resin content,different sintering temperatures,and the effects of different heating rates on the properties of wood ceramics were compared through the changes in carbon yield,volume shrinkage,flexural strength,volume resistivity,degree of graphitization,chemical structure,and microscopic morphology of wood ceramics.And the differences in performance between wood ceramics prepared from poplar tension wood and wood ceramics prepared from normal poplar were compared.The main conclusions of the paper are as follows:When the content of the phenolic resin in the precursor gradually increased,the carbon yield of wood ceramics increased gradually,the volume shrinkage rate gradually decreased,the pore wall gradually increased from thin to thick,and the flexural strength gradually increased,and the volume resistivity gradually decreased.In the process of high-temperature sintering,the precursor is carbonized while being thermally decomposed,and the content of phenolic resin has no obvious influence on the degree of graphitization.As the sintering temperature gradually increased(from 700 °C to 900 °C),the carbon yield of wood ceramics gradually decreased,the volume shrinkage rate gradually increased,the pores became denser,and the continuous phase of glassy carbon gradually increased,and the flexural strength gradually increased.The volume resistivity decreased rapidly from the maximum,and the increase in the sintering temperature was beneficial to the increase of the degree of graphitization.There were C,H,O,and other elements in wood ceramics.During high-temperature carbonization,with the acceleration of the heating rate(from2°C/min to 6°C/min),the acceleration of the pyrolysis rate of the raw materials reduced the yield of wood ceramic carbon and increased the volume shrinkage rate,the fusion degree of the vitreous carbon and amorphous carbon decreased,the pore section became rougher on the microstructure,the flexural strength decreased gradually,and the volume resistivity increased gradually.With different heating rates,the carbon yield,flexural strength,and graphitization degree of the tension wood ceramics were higher than those of the normal wood ceramics,and the volume shrinkage and volume resistivity were lower than those of the normal wood ceramics.Above all,when tension wood was used in the preparation of wood ceramics,the carbon yield,dimensional stability,and mechanical properties of wood ceramics of poplar tension wood were higher compared with normal wood.This provides a theoretical basis for improving the use efficiency of poplar tension wood and enriching the raw materials of wood ceramics.