120 / 2021-11-10 23:10:24

HEMICELLULOSE-RICH TRANSPARENT WOOD: MICROSTRUCTURE AND MACROSCOPIC PROPERTIES

Transparent wood,Hemicellulose,Microstructural characteristics,Optical performance,Mechanical strength

Hemicellulose plays a vital role in nature wood matrix through regulating the spatial organization of cellulose fibrils and interacting with lignin. Here, we for the first time demonstrate the significance of hemicellulose for improving the microstructure and macroscopic properties of transparent wood (i.e. wood/polymer composite), an emerging structural material. A delignified wood templet with high hemicellulose content (~13 wt%) and well-preserved cellulose supramolecular structure was prepared via a peracetic acid-based process. This hemicellulose-rich delignified wood templet possesses nearly intact cell wall structure and sufficient space in the lumen and middle lamella for polymer space-filling. Consequently, the resultant hemicellulose-rich wood/PMMA composite exhibits high optical transmittance (~85%), medium haze (~72%), acceptable optical stability as well as excellent mechanical strength (tensile strength of 165.3 MPa and toughness of 1.65 MJ/m³), benefitting from the absence of microstructural defects and heterogeneity in the matrix. In combination with its eco-friendly and efficient preparation, this hemicellulose-rich transparent wood with admirable optical and mechanical performances holds huge potential for a range of applications, such as energy-efficient buildings and optical devices.