| China has abundant bamboo resources,and bamboo product processing technology has reached the world’s leading level.With the development of the bamboo product processing industry,problems such as low utilization rate of bamboo materials and waste of bamboo resources have become increasingly prominent.In this paper,by-product bamboo powder in the processing of bamboo products,liquefied resin treatment.Then,a foaming process is used to perform a foaming test on the bamboo powder liquefied resin to prepare a biomass foaming resin material.Finally,the resin material is modified to prepare bamboo powder liquefied resin foaming cultivation matrix material that can be used in agricultural production,and the preparation process parameters of each link are optimized.The main content of the thesis research includes the following aspects:(1)Through orthogonal test,it was found that during the process of liquefaction and resinization,the greatest impact on the residue rate of bamboo powder liquefaction resin was the liquefaction temperature,and the greatest impact on the viscosity of bamboo powder liquefaction resin was the resinization temperature.Through FT-IR characterization,it was found that under the conditions of too high temperature,long liquefaction time,and excessive catalyst addition,the small molecule active substances produced by the liquefaction of bamboo powder will continue to undergo polycondensation reactions,forming new macromolecular substances,resulting in liquefaction residue The rate increases while reducing the activity of liquefied products.The optimal liquefaction resinization conditions obtained by the study are:liquefaction time is 20 min,liquefaction temperature is 115℃,catalyst addition is 25 parts,resinization time is 30 min,and resinization temperature is 90℃.The residue rate of bamboo powder liquefied resin is 0.57%,viscosity 3760 m Pa·s,hydroxyl value 98.33mg KOH/g.(2)The foaming experiment of bamboo powder liquefied resin using response surface design found that:in single factor analysis,the amount of curing agent added had the most significant effect on the compressive strength of the foamed material;in the interaction analysis,the amount of curing agent added and isocyanate(PM-200)The interaction effect of the added amount is the most significant.The optimal foaming material preparation process parameters obtained from the experiment are:When the addition amount of surfactant is 9 parts,the addition amount of foaming agent is 16parts,the addition amount of curing agent is 30 parts,and the addition amount of PM-200 is 45 parts,the overall performance of bamboo powder liquefied resin foam material is excellent.The compressive strength is 96.4 k Pa,the bending breaking load is 4.9543 N,the bending deformation is 5.526 mm,and the maximum tensile strength is 48.1 k Pa.The foam material prepared with the above parameters has the characteristics of better cell structure,better reaction process,and good thermal stability.(3)By adding polyether polyol to the bamboo powder liquefied resin to modify it,and adjusting the proportion of foaming additives accordingly,the powdering phenomenon of the bamboo powder liquefied resin foaming material is well reduced,and excellent comprehensive performance is obtained Foaming cultivation matrix material.The optimal preparation process parameters are:resin addition amount is 30wt%,curing agent addition amount is 7.5 wt%,PM-200 addition amount is 20 wt%,polyether polyol addition amount is 1 wt%.The bamboo powder liquefied resin foaming cultivation matrix material prepared by the above process parameters has an apparent density of 0.0419 g/cm~3,a leaching p H of 2.61,a water absorption rate of0.8593 g/cm~3,a water retention rate of 97.6842%,and a longitudinal crush strength0.0511 k Pa,the transverse crimping strength is 0.0424 k Pa.(4)The study found that after adding polyether polyol,the pulverization of bamboo powder liquefied resin foaming cultivation matrix material is much reduced,with a good cell structure and good thermal stability.In the application test,it is found that the cultivation substrate material has good stability both indoors and outdoors.The test seeds can germinate well on the substrate,and the root system of the seedling can grow in the cultivation substrate. |
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