Study On The Preparation And Properties Of Buried-treated Wood

Buried wood as an extremely valuable wood resource has a high scientific and cultural values in nature,it is known as the mummy of plantae.which is aromatic and pyknotic,colorful and beautiful,at the same time,it has high decay resistance.In this paper,by considering the causes of formation of buried wood and simulating the formed micro-ecological environment,the fast-growing wood was treated and prepared to a new type of green and high-quality preservative-treated wood��Buried-treated wood.In this study,firstly,the performances of the buried wood(Phoebe sp.)and fast-growing wood(Populusbeijingensis and Cunninghamia lanceolata)were compared,afterwards,the main properties and chemical compositions of were analyzed for buried wood and fast-growing wood.Then,based on the matrix soil synthesized by the nano-materials and the plant extract,the wood was buried in this soil under a certain temperature,time and vacuum conditions,in order to prepare the buried-treated wood.Then,the decay resistance of this wood was analyzed and evaluated.Finally,the microstructure,chemical structure,elemental changes,and preservative-treated mechanism of the buried-treated wood were analyzed by scanning electron microscope(SEM),energy dispersive X-ray spectroscopy(EDX),Fourier transform infrared spectrometer(FTIR),and X-ray diffractometer(XRD).The main results of this study are summarized below:1.In this study,the density,decay resistance,microstructure,and chemical characterization of the buried wood(Phoebe sp.),poplar(Populusbeijingensis W.Y.Hsu)and fir(Cunninghamia lanceolata(Lamb.)Hook)were analyzed.The results shown that,the density of buried wood was larger than the poplar and fir,After the same period of decay resistance test,the decay resistance of buried wood was much better than the other two woods.The buried wood had many crystals in the cell wall and the hemicellulose was partially degraded and had a high degree of crystallinity.The calcium carbonate content of buried wood was higher than the fast-growing wood,and the type of calcium carbonate belonged to calcite type.2.In this study,single-factor experimental design and orthogonal experimental design were used to control the ratio of nano-calcium carbonate,tung oil and soil in the synthetic substrate soil,and the treatment temperature and treatment time were adjusted to prepare the buried-treated wood.The results shown that,buried treatment could significantly increase the WPG,density and decay resistance of wood.In the orthogonal design,the decay resistance grades of buried-treated wood were reached to the level of resistant class,after verification,the addition amount of nano-calcium carbonate was 25g,the addition amount of tung oil was 300g,the treatment temperature was 175�C,and the treatment time was 7h,the highest WPG of buried-treated wood reached to 140.61%,the highest density reached to 1.024g/cm~3,the weight loss rate was lowest to 4.95%,the decay resistance was increased by 89.77%,the wood could be ranked as highly resistant class of wood decay.3.In this study,the scanning electron microscope(SEM),energy dispersive X-ray spectroscopy(EDX),Fourier transform infrared spectrometer(FTIR),and X-ray diffractometer(XRD)were used to compare the detection and analysis of buried preservative-treated wood and untreated wood,these results were to explore the mechanism of preservative treatment and chemical changes.The results showed that,the tung oil and nano-calcium carbonate effectively entered the interior of the wood by the encasing treatment of the mixed soil and buried treatment,the two substances could chemically combine with wood and evenly distribute on the vessel of wood,the content of trace elements was changed,simultaneously,the inner wall of the cell wall has formed high polymer due to the infiltration of tung oil,it had become extremely smooth.These changes made the characteristic peak functional groups of wood be changed,Finally,the amorphous area of the treated wood was changed,the peak spacing became wider,and the crystallization peak of calcite type calcium carbonate appeared.