| As is well known, wood supply can't meet the demand of wood based panel industry in our country, and this situation is becoming even worse recent years. More and more wood based panel factories have to cease production for being lack of raw material. Fortunately China has plenty of agricutrual straws, and many kinds of them such as wheat straw, rice straw and so on, have being studied on the possibility of being as raw materials for panel-making, hoping to ease the raw material shortage problem.This essay are mainly discussed the wettability of cotton stalk and the possibility of medium density fiberboard made from Cotton stalk, which is considered as the most approximate raw material to wood on the basic properties. Poplar is also studied as control sample in the experiments. The contents and conclusion of my study are as follows:1 First, the wettability of cotton stalk and poplar with different heat treatments is studied. The results show that the wettability of heat-treated samples decreased, and the polarity of cotton stalk is stronger than that of poplar, which means that the wettability of water-soluble adhesives such as UF on cotton stalk is better than that on poplar. And results from those are related to the lewis based surface free energy (γ_s~-) of material. The higher the γ_s~- of material, the better the wettability of polar liquds on the material.2 The effect of cotton stalk/ poplar fiber with different mixing ratios on the curing of UF are studied by heat analysis. Through the results we get that methylene-ether linkages will decompose into methylene bridges during UF curing, through which reaction UF will become more stable. And the effect of cotton stalk /poplar fiber mixing ratio on the degree of methylene-ether linkages decomposing into methylene bridge are 4:0>3:1>0:4>1:3>1:1.3 The processing technology of MDF made from cotton stalk is studied. And through Orthorhombic experiment we get that the optimum parameters of glue adding, hot-pressing...
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