Study On The Synergistic Treatment Technology Of Antibacterial And Dimensional Stabilization Of Dillenia Indica Wood

Dillenia indica wood has excellent physical properties and beautiful color,which is often used to make high-end furniture and decorative materials.However,due to the high moisture content of Dillenia indica wood,it is easy to deform,warp and crack after processing,and the wood is rich in nutrients that harmful fungi like to eat,which is easy to be affected by the erosion of fungi and insects,which affects the service life and causes a lot of waste of resources.In order to broaden the application range of Dillenia indica wood in practical engineering,this study first analyzed the structure and properties of Dillenia indica wood,and then prepared polyethylene glycol(PEG),silica sol,borate and crosslinking agent according to a certain proportion.The modifier was immersed in the wood by vacuum pressure,and the temperature was controlled to form a cross-linked network in the wood.Finally,it was dried by different media such as air,paraffin and silicone oil to prepare high-quality wood with good dimensional stability,mildew resistance and strong resistance to loss.The main results are as follows:(1)The density of Dillenia indica wood was medium,and the absolute dry density was 0.591 g/cm~3.The drying speed was fast,and the radial shrinkage and wet expansion during the drying process were much smaller than the tangential direction.The hot water extract was more than the cold-water extract,the alkali extract was 14.26%.The parenchyma cells were rich in a large number of water-soluble spherical starch granules and water-insoluble needle bundles,and the longitudinal permeability was better.(2)When PEG,silica sol,borate and crosslinking agent L were compounded with 20%,30%,2%and 8%of the total weight of the solution,respectively,the swelling rate and water loss rate of the polymer were the smallest.Infrared spectroscopy and scanning electron microscopy analysis showed that silica sol could react with borate and crosslinking agent,while PEG was only physically adsorbed in the gel crosslinking network structure;the pressure impregnation treatment of Dillenia indica was carried out by compound agent and single agent respectively.The first anti-swelling rate of the composite agent modified material reached 46.23%in three water absorption-drying cycles,but the anti-swelling performance decreased significantly after three water absorption-drying cycles.About40.59%of the agent was lost,which failed to improve the dimensional stability of Dillenia indica wood in a long term.(3)Paraffin and silicone oil were used to dry the impregnated wood in the previous chapter.Compared with the drying wood,the weight gain rate and compatibilization rate were further improved.The hydrophobicity of the wood was greatly enhanced.The water absorption equilibrium moisture content was reduced by 26.8%and 23.6%,respectively.The water contact angle increased by 118.3°and 116.5°,respectively.The decrease of water absorption limited the loss of PEG.After three water absorption-drying cycles,the retention of wax-dried and oil-dried modified wood was105.7%and 100.3%higher than that of drying wood,and the dimensional stability increased by125.7%and 135.1%.From the comprehensive anti-mildew experiment of modified wood,it can be seen that the addition of borate in the modifier greatly improved the anti-mildew performance of Dillenia indica wood,and the formation of gel inside the wood also limited the loss of borate,making it have long-term anti-mildew performance.