Review On The Modification And Performance Of Bamboo Or Wood

Since bamboo and wood are natural porous materials,they are prone to a series of dimensional instability such as cracking or deformation.While enjoying designing,using and making various kinds of bamboo and wood products,how to make bamboo products colorful,antiseptic and mothproof is a great challenge we've been faced for a long time.In this paper,the performance of bamboo,Chinese fir,poplar and monterey pine derived by maleic anhydride in different solvents of the same sodium phosphate was compared,and then compared with maleic anhydride and glycerol composite modification.finally.the hot pressing process optimized by different temperature,time and pressure factors.support for materials esterification process and heat treatment process optimization and dimensional stability and physical and mechanical properties regulation;The color and crystallinity of chemical treatment materials,the hydrophobic properties and luster changes of physical modified materials were analyzed,and the dimensional stability changes of materials before and after modification were investigated.Next,the instruments of FTIR,TG,DSC,SEM,and mechanical testing machine,etc.were applied to study on chemical composition and group change,thermal stability,microstructure and dynamic thermodynamic properties of modified bamboo/wood.The main conclusions are as follows(1)The effects of maleic anhydride treated four materials on the weight gain,dimensional stability,color and crystallinity of acetone(Act)and dimethylformamide(DMF)were compared.The results indicated that them in DMF group obtained higher weight percentage gain(19.92%.69.62%,39.16%and 36.98%)than that of Act group(15.46%,59.21%,31.3%and 35.5%),the dimensional stability of the DMF group can be increased by less than the Act group.Compared with before treatment,the specimens of DMF group were slightly yellowish,and the Act group was somewhat reddish.The crystallinity of Act group degree of decreased,which was slightly larger than that of DMF group,and a non-cellulosic lattice characteristic diffraction peak appeared around 20 of 28.5°.(2)Bamboo,Chinese fir,Poplar and Monterey pine after pretreatment at 90? for 4h with maleic anhydride then were relatively reacted with glycerol under at 100? for 6h.The highest weight gain rate of the four composite treatment materialswas fir(79.19%),and the lowest capacity increase rate was bamboo(5.94%),and the anti-volume expansion ratio relatively reached 43.2%.44.8%.46.4%and 59.4%.The thermal stability performance of the four MA/G composite treatment materials is better than that of the MA monomer modified materials.Compared with the untreated materials.the pyrolysis rate is relatively slow,and the thermal stability can be improved stepwise.FTIR showed that the intensity of the C=O,C-O and C=C absorption peak in the MA-G treated sample was much greater than that of the untreated.According to the SEM,the cross-section of the composite treated materials showed no obvious cell structure deformation compared with the control,but the treated bamboo appeared brittle fracture and the diameter and the pit of the treated Chinese fir were not clear in the longitudinal section,resulting in an increase in dimensional stability of the material(3)Bamboo,Chinese fir,Poplar and Monterey pine specimens conditioned at 65%humidity were subjected to heat treatment at temperatures at 280,300,320 and 340? for 5 and 10s.The brightness L*was averaged at 81.45,72.82,86.98,79.59 units of untreated respectively fell to a minimum at 28.71,40.1,32.27,43.67 units.The hygroscopicity of the four materials is also gradually reduced,the maximum relatively decline rates are 47.1%,42%,57.25%,54.3%.The surface hydrophobicity is significantly improved;With regard to the surface gloss,the appearance with downward trend of bamboo and the rising trend of wood,the maximum relatively change rate are 50%,45.83%,57.6%and 50.85%.Under the test conditions,the maximum increase in compressive strength of the grain was bamboo,which was 40.75%;the maximum rate of increase in flexural strength was 61.57%,which was poplar;The flexural modulus of elasticity of pine increased by 31.23%.The three physical quantities of fir increased by 20.15%,27.09%and 27.45%.Finally,it is concluded that the processing temperature factor has a significant impact on the performance characterization of the test than the processing time factor.