Preparation and characterisation of gelatine-nano-SiO 2 mineralised poplar-wood composites

Fast-growing poplar wood is characterised by its low density and poor dimensional stability. Biomimetic mineralisation using nano-SiO2 shows significant potential; however, challenges remain regarding nanoparticle dispersion and interfacial adhesion. In this study, sol–gel chemistry, vacuum-pressure impregnation, and low-voltage electrostatic field assistance were employed to successfully fabricate gelatine-nano-SiO2 mineralised poplar composites (GSP), thereby enhancing the wood’s performance through improved integration of nanoparticles. The results showed that GSP exhibited a higher absolute dry density (490 kg·m−3) and reduced swelling (radial: 0.5%; tangential: 2.2%) relative to untreated poplar wood (420 kg·m−3, radial: 3.9%; tangential: 6.1%), and hygroscopicity was reduced from 85% to 46%. Surface analysis revealed reduced brightness, increased chromaticity, and improved wettability in GSP. Fourier-transform infrared spectroscopy (FTIR) confirmed chemical bonding between SiO2 and the poplar cell walls, while Thermogravimetric analyser (TGA) demonstrated enhanced thermal stability. Scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) confirmed uniform SiO2 distribution within GSP. These improvements demonstrate the efficacy of bioinspired design in enhancing wood performance. This approach provides a scalable and environmentally sustainable pathway for the development of high-value wood composites.