Study on Physical and Mechanical Properties of Poplar Modified by Phenol-formaldehyde Resin

来源 :Chinese Forestry Science and Technology | 被引量 : 0次 | 上传用户:yunzh
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Impregnation method can effectively improve physical and mechanical properties of wood. In this study, plantation poplar lumbers are impregnated by a low molecular weight phenol-formaldehyde resin solution with concentration of 30% under vacuum-pressure process, and then dried and machined according to the related standards. The results show that the physical and mechanical properties of poplar can be improved by the treatment, except for toughness. The average density of poplar increases from 0.397 to 0.710 g/cm3, the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain of treated specimens increase by 56.71%, 112.97% and 87.69%, respectively, compared to the untreated. And the hardness values on radial and tangential sections, and nail holding power as well as abrasion resistance of treated specimens improve by 283.87%, 82.78%, 71.43% and 22.06%, respectively; while toughness decreases by 48.80%. Impregnation method can effectively improve physical and mechanical properties of wood. In this study, plantation poplar lumbers are impregnated by a low molecular weight phenol-formaldehyde resin solution with concentration of 30% under vacuum-pressure process, and then dried and machined according to the related standards. The results show that the physical and mechanical properties of poplar can be improved by the treatment, except for toughness. The average density of poplar increases from 0.397 to 0.710 g / cm3, the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain of Treated specimens increase by 56.71%, 112.97% and 87.69% respectively respectively, compared to the untreated. And the hardness values ​​on radial and tangential sections, and nail holding power as well as abrasion resistance of of specimens improve by 283.87%, 82.78%, 71.43% and 22.06% respectively; while while toughness decreases by 48.80%.
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