Flax fiber(FF) was used to reinforce wood flour/high density polyethylene composites(WF/PE).WF/PE particles were uniformly mixed with FF via high-speed mixing and then extruded with a single screw extruder to prepare ...Flax fiber(FF) was used to reinforce wood flour/high density polyethylene composites(WF/PE).WF/PE particles were uniformly mixed with FF via high-speed mixing and then extruded with a single screw extruder to prepare FF reinforced WF/PE composites(FF/WF/PE).Mechanical testing,dynamic mechanical analysis,scanning electron microscopy(SEM),creep measurement and Torque rheology were used to characterize the resulting composites.The results indicate that the mechanical performance of the composites could be remarkably improved by adding a limited amount of FF.The flexural strength and modulus increased by 14.6 and 51.4%,respectively(FF content of 9 wt%),while the unnotched impact strength could be increased by 26.5%(FF content of12 wt%).The creep resistance and toughness of thecomposite was markedly improved without changing the plastic content of the composite material.展开更多
This study investigated the characteristics of wood fiber/polycaprolactone composite after an artificial accelerated thermo-oxidative aging treatment.The effect of time,temperature and humidity during the treatment on...This study investigated the characteristics of wood fiber/polycaprolactone composite after an artificial accelerated thermo-oxidative aging treatment.The effect of time,temperature and humidity during the treatment on their mechanical,chemical and morphology properties were evaluated.The composite was prepared from melted wood fibers and modified polycaprolactone by a molding process.A temperature and humidity controllable test chamber was used for the thermo-oxidative aging of the composite.The thermo-oxidative aging caused surface of the composite to be much more rougher and even a few cracks and holes appeared on it.According to the spectra of Fourier Transform Infrared(FTIR)and Gel Permeation Chromatography(GPC),C=O in the molecular chain of polycaprolactone was hydrolyzed and C–O was broken after the aging treatment,which resulted in a reduction in average molecular weight of the composite.Moreover,results showed that the mechanical strength decreased a lot with the increase in time,temperature and humidity,and the effect of temperature and humidity was more significant compared with that of time.Controlling the temperature and humidity during thermo-oxidative aging treatment could accelerate the aging of composite,which provided a quick and effective method for evaluating the aging resistance of the composite.展开更多
In order to solve the problem of poor thermal insulation in the current wood-plastic building,two kinds of structural wood wall integrated with wood plastic composite(WPC)are designed,and the thermal insulation perfor...In order to solve the problem of poor thermal insulation in the current wood-plastic building,two kinds of structural wood wall integrated with wood plastic composite(WPC)are designed,and the thermal insulation performances of the walls are studied.The results show that the WPC integrated wall with frame-shear structure has a good stability,and the excellent performance of the WPC can be fully realized.Wall studs and wall panels are important factors affecting the thermal performance of the walls.Wood plastic materials can meet the thermal performance requirements of the walls.The single-layer frame walls and double-layer frame walls integrated with the WPC both have a good thermal performance.According to‘Design Standard for Energy Efficiency of Public Buildings(GB 50189-2015)’,the heat transfer coefficient of the single-layer frame wall integrated with 20 mm thick WPC wall boards and WPC wall studs is 0.414 W/(m^(2)•K),which can meet the standard of wall thermal levelⅡt and is suitable for cold areas.The heat transfer coefficient of the double-layer frame wall integrated with 50 mm thick WPC wall panel and WPC wall studs is 0.207 W/(m^(2)•K),which can meet the standard of wall thermal levelⅠt and is suitable for severe cold areas.展开更多
The sound insulation performance is an important technical index for evaluating the physical property of the building wall.Three kinds of structural wood walls integrated with wood plastic composite(WPC)were designed....The sound insulation performance is an important technical index for evaluating the physical property of the building wall.Three kinds of structural wood walls integrated with wood plastic composite(WPC)were designed.And the sound insulation performance of the walls was studied.The results showed that for the wall that constructed by the WPC as the wall studs,compared with the one that constructed by the pine wood as the wall studs,the deviation of their sound insulation was lower than±3 dB.The wall’s external panel material had significant effect on the wall’s sound insulation property,and the contribution of the wood-plastic panel to the sound insulation was much higher than that of the polyvinyl chloride(PVC)plastic hanging board.The surrounding sealing quality of the wall’s external panel material had an important influence on the sound insulation effect of the building wall,and the panel of the wood plastic interior wall had less influence on the sound insulation performance of the wall.Taking the sound-absorbing cotton or non-woven fabric as elastic strips was an effective technical measure to improve the sound insulation performance of the walls.The sound insulation was improved by 2.4 dB and 3.1dB respectively after the correction of pink noise spectrum,and increased by 2.8 dB and 3.6 dB respectively after the correction of traffic noise spectrum.展开更多
基金supported by the Natural Science Foundation of China(Grant No.31600459)the Natural Science Foundation of Heilongjiang Province of China(Grant No.C2016001)
文摘Flax fiber(FF) was used to reinforce wood flour/high density polyethylene composites(WF/PE).WF/PE particles were uniformly mixed with FF via high-speed mixing and then extruded with a single screw extruder to prepare FF reinforced WF/PE composites(FF/WF/PE).Mechanical testing,dynamic mechanical analysis,scanning electron microscopy(SEM),creep measurement and Torque rheology were used to characterize the resulting composites.The results indicate that the mechanical performance of the composites could be remarkably improved by adding a limited amount of FF.The flexural strength and modulus increased by 14.6 and 51.4%,respectively(FF content of 9 wt%),while the unnotched impact strength could be increased by 26.5%(FF content of12 wt%).The creep resistance and toughness of thecomposite was markedly improved without changing the plastic content of the composite material.
基金The work was supported by National Key R&D Plan Project(2017YFD0601200)Hunan Key R&D Plan Project(2017SK2334)of College of Materials Science and Engineering,Central South University of Forestry and Technology.
文摘This study investigated the characteristics of wood fiber/polycaprolactone composite after an artificial accelerated thermo-oxidative aging treatment.The effect of time,temperature and humidity during the treatment on their mechanical,chemical and morphology properties were evaluated.The composite was prepared from melted wood fibers and modified polycaprolactone by a molding process.A temperature and humidity controllable test chamber was used for the thermo-oxidative aging of the composite.The thermo-oxidative aging caused surface of the composite to be much more rougher and even a few cracks and holes appeared on it.According to the spectra of Fourier Transform Infrared(FTIR)and Gel Permeation Chromatography(GPC),C=O in the molecular chain of polycaprolactone was hydrolyzed and C–O was broken after the aging treatment,which resulted in a reduction in average molecular weight of the composite.Moreover,results showed that the mechanical strength decreased a lot with the increase in time,temperature and humidity,and the effect of temperature and humidity was more significant compared with that of time.Controlling the temperature and humidity during thermo-oxidative aging treatment could accelerate the aging of composite,which provided a quick and effective method for evaluating the aging resistance of the composite.
文摘In order to solve the problem of poor thermal insulation in the current wood-plastic building,two kinds of structural wood wall integrated with wood plastic composite(WPC)are designed,and the thermal insulation performances of the walls are studied.The results show that the WPC integrated wall with frame-shear structure has a good stability,and the excellent performance of the WPC can be fully realized.Wall studs and wall panels are important factors affecting the thermal performance of the walls.Wood plastic materials can meet the thermal performance requirements of the walls.The single-layer frame walls and double-layer frame walls integrated with the WPC both have a good thermal performance.According to‘Design Standard for Energy Efficiency of Public Buildings(GB 50189-2015)’,the heat transfer coefficient of the single-layer frame wall integrated with 20 mm thick WPC wall boards and WPC wall studs is 0.414 W/(m^(2)•K),which can meet the standard of wall thermal levelⅡt and is suitable for cold areas.The heat transfer coefficient of the double-layer frame wall integrated with 50 mm thick WPC wall panel and WPC wall studs is 0.207 W/(m^(2)•K),which can meet the standard of wall thermal levelⅠt and is suitable for severe cold areas.
基金This work was supported by Anhui Sentai WPC Group Co.Ltd.and Priority Academic Development Program of Jiangsu High Education Institutions(PAPD).
文摘The sound insulation performance is an important technical index for evaluating the physical property of the building wall.Three kinds of structural wood walls integrated with wood plastic composite(WPC)were designed.And the sound insulation performance of the walls was studied.The results showed that for the wall that constructed by the WPC as the wall studs,compared with the one that constructed by the pine wood as the wall studs,the deviation of their sound insulation was lower than±3 dB.The wall’s external panel material had significant effect on the wall’s sound insulation property,and the contribution of the wood-plastic panel to the sound insulation was much higher than that of the polyvinyl chloride(PVC)plastic hanging board.The surrounding sealing quality of the wall’s external panel material had an important influence on the sound insulation effect of the building wall,and the panel of the wood plastic interior wall had less influence on the sound insulation performance of the wall.Taking the sound-absorbing cotton or non-woven fabric as elastic strips was an effective technical measure to improve the sound insulation performance of the walls.The sound insulation was improved by 2.4 dB and 3.1dB respectively after the correction of pink noise spectrum,and increased by 2.8 dB and 3.6 dB respectively after the correction of traffic noise spectrum.
