Micro-mechanical Properties And Dynamic Wettability Of Fast-growing Poplar Wood

As the important part of National Natural Science Foundation–funded project"Study on the change rule of the cell surface chemical group and cell wall MOE for wood and straw fiber adjusted and controlled by enzyme", this paper focuses on the effect of pre-compressed process on the micro-mechanical properties of cell wall and the dynamic wettability of poplar wood surface.The micro-mechanical properties of cell wall were studied in this research by using atomic force microscope (AFM) and nanoindentation. The hardness and elastic modulus of the fast-growing poplar cell wall were investigated by nanoindentation. The effect of hot pressing parameters (including compression ratio, plate temperature, time of holding) on the micro-mechanical properties of fast-growing poplar cell wall was also reported. The basic dimensions including cell wall thickness and length were characterized by AFM. Model of cell structure and the mathematical model based on the nanoindentation were set up, using plane analytic geometry, to show the relationship between loading and the distortion of cell.Dynamic wettability of fast-growing poplar wood surface was also reported in detail in this investigation. The Model formula has been set up to reveal the dynamic wettability of wood and wood-based materials surface, as well as the effect of common adhesive (including Urea formaldehyde resin, UF Resin and Phenol formaldehyde resin,PF Resin) on the dynamic wettability of fast-growing poplar wood surface with different growth ring or latewood and earlywood in the same growth ring was explored. What's more, the effect of hot pressing parameters (including compression ratio, plate temperature, time of holding) on the dynamic wettability of fast-growing poplar wood surface was also reported by the using of model formula.The objective of this theme is to give a close study on the compress mechanism of fast-growing poplar wood by using micro-mechanics and dynamic wettability theory. The research is on the purpose of define and perfect the theory related to the compress technology of fast-growing poplar wood. Meanwhile, it has practical value to provide theoretical support for the improvement and combined machining of fast-growing poplar wood as well as other wood species.