Ultraviolet-Shielded\nTransparent Wood with Improved\nInterface for Insulating Windows

Recently, transparent wood (TW) has\nbeen considered for many energy-efficient\nbuilding products, such as windows and decorations. However, the existing\nTW still faces issues with size and thickness, as well as problems\nwith functional fillers affecting the optical and mechanical properties\nof TW, which limits its wide application in the window products. In\nthis study, a wood composite material (WCM) with good optical, mechanical,\nand thermal insulation and UV-shielding properties was prepared by\nusing delignified wood (DW), methyl methacrylate (MMA), and 4-vinylphenylboric\nacid (VPBA). Compared with NaClO<sub>2</sub> delignification, peracetic\nacid (PAA) preserves hemicellulose and a more stable pore structure,\nwhich facilitates the filling of polymers into the DW template, resulting\nin the preparation of more extensive and thicker TW. VPBA, as a functional\nraw material for UV shielding, on the one hand, improves the interfacial\ncompatibility of the TW, thus improving the optical properties (transmittance\nof about 90%, haze of about 55%) and mechanical properties (64.5 MPa).\nOn the other hand, WCM was found to effectively block UV–C,\nUV–B (about 100%), and UV-A (about 90%) radiation while maintaining\nsufficient visible light transmittance. In addition, as an insulating\nwindow, WCM has low thermal conductivity and can maintain a high temperature\nfor a long time after the loss of solar radiation, which is an ideal\nthermal insulation material and is expected to become a potential\nsubstitute for conventional glass.