Study On Impregnation Process And Drying Benchmark Of Furfuryl Alcohol Resin Impregnated Fast-growing Poplar Wood

The low molecular weight resin impregnation treatment technology is an effective method to improve the performance of wood,and has become the research and focus of domestic research institutions and production enterprises.In this study,the fast-growing poplar wood planted widely in China was used as a test material,and the furfuryl alcohol resin was used as a modifier to modify the poplar wood by vacuum pressure impregnation method,the effects of sterol impregnation on its mechanical properties,dimensional stability,durability and micromorphology were studied,and the suitable ratio of furfuryl alcohol resin impregnating solution was determined.On this basis,the relationship between impregnation process parameters and poplar impregnation effect was studied by response surface design and analysis method,and then the impregnation process was optimized.Finally,the drying standard and drying characteristics of 25 mm thick furfuryl alcohol resin impregnated materials were discussed.It aims to provide a certain theoretical basis and technical support for the industrial production of poplar furfuryl alcohol resin impregnated materials.The main research contents and results are as follows:(1)The furfuryl alcohol immersion liquid with maleic anhydride and citric acid as catalysts and different ratios was prepared as a modifier,and the poplar wood was treated by vacuum pressure impregnation method.The weight gain rate,static bending strength,elastic modulus,hardness,dry shrinkage,swell,water absorption,mildew resistance,anti-blue denaturation,corrosion resistance,termite resistance and microscopic morphology are the evaluation indicators.The influence of sterol impregnation on its mechanical properties,dimensional stability and durability was determined.The suitable ratio of sterol resin impregnating solution was determined.The results indicated that the mechanical properties,dimensional stability and durability of the fast-growing poplar wood of the plantation were significantly improved after impregnation with furfuryl alcohol resin.When the impregnation liquid is 2%maleic anhydride as the catalyst and the sterol resin mass fraction is 50%,the mechanical properties and dimensional stability of the impregnated material are the best,that is,the sterol resin has the best modification effect.After immersion treatment,the sterol resin not only enters the cell cavity and cell gap of the wood,but also fills the pores of the cell wall and keeps the cell wall inflated for a long time,blocking the passage of water movement,which helps to improve the mechanical properties,dimensional stability and durability of poplar.(2)The optimized artificial formula was used as the impregnation liquid,and the rapid-intensity poplar wood samples were treated by vacuum pressure impregnation method.The relationship between the impregnation process parameters and the poplar impregnation effect was studied by using Design Expert through response surface design and analysis method.Optimized vacuum pressure impregnation process.The results indicated that the analysis of variance obtained by Design Expert showed that there was a significant correlation between the process factors established by the binary regression model and the weight gain rate of the specimens.The model could be used to predict the weight gain rate of poplar specimens under certain conditions.The predicted value of the model had little error with the actual value.The degree of vacuum(A),vacuum time(B),immersion pressure(C),and pressurization time(D)had a significant effect on the rate of weight gain and the interaction terms AB,AC,AD,BC,BD,and CD of the above factors had less influence on the weight gain rate.The binary regression fitting equation with the weight gain rate(Y)of poplar specimens as the response value was determined as:Y=61.10+0.82A+2.45B+2.13C+1.56D-3.82B2-2.07C2-3.00D2.The optimum process parameters for the vacuum impregnation of the fast-growing poplar wood modified by furfuryl alcohol resin were as follows:vacuum degree was 0.08MPa,vacuum time was 1.00h,impregnation pressure was 0.70MPa,and pressurization time was 3.00h.The average weight gain obtained was 61.25%.(3)The optimized formula was used as the impregnation liquid,and the artificial forest fast-growing poplar furfuryl alcohol resin impregnated material was prepared by the optimized vacuum pressure impregnation process.The drying characteristics of the impregnated materials and materials were compared and analyzed by 100? test method.The drying process of 25mm plantation fast-growing poplar furfuryl alcohol resin impregnated material was explored.The results indicated that after the immersion treatment with furfuryl alcohol resin,the drying characteristics of the immersion material were significantly different from those of the material.The initial cracking,internal cracking,section deformation and distortion were significantly reduced.The dry basis of the 25mm thick plantation fast-growing poplar furfuryl alcohol sterol resin impregnated material was established.The dipping material was dried from the initial moisture content of about 80%to the final moisture content of 8.12%,which took 21d,and the dry quality was excellent.All meet the national standard primary material requirements...