Efficient preparation and properties of wood fiber transparent materials with powdered wood

At present, since wood resources are in short supply, it is of great significance to utilize wood residues to prepare bio-composites for sustainable developments. Compared with the preparation of traditional transparent materials using solid wood, making transparent materials using wood fibers (WF) can utilize wood residues (such as wood chips, wood strips, sawdust, etc.) as the raw material sources, which can help the environmental protection and promote energy saving features of transparent fiber wood (TFW). Currently, the method of making TFW usually uses simple chopped wood residues with the removal of lignin. The transparent composites using WF were prepared by impregnating pre-polymerized polymers. Therefore, this study adopted a method of wood powders (WPF) screening to solve this problem. The wood residues were smashed into a certain mesh size of WPF, and then the epoxy resin (EP) was impregnated into the delignified WPF to successfully prepare the wood powder-reinforced transparent wood (TCWP), which effectively optimized the preparation process and improved the efficiency. The preparation efficiency is greatly improved by more than 50%. The effects of length-diameter ratio and mass fraction of WPF on optical properties, mechanical properties and thermal conductivity of TCWP were further investigated in this study. The comprehensive analysis showed that, when the WPF size was 80 mesh and the fiber mass fraction was 5%, it had the best optical, thermal, and mechanical properties. In addition, the laser scattering experiments showed TCWP can be used as an optical screen and architectural glass in the engineering practice and became a transparent composite material with high added value, because of the uniformity of WPF dispersion in EP, resulting in more uniform light passing rate and increased haze.