Enhancing poplar-wood properties through nano-silica fortified polyvinyl-acetate impregnation

Abstract

ABSTRACT The effects of pressure impregnation of nano-SiO2 fortified polyvinyl acetate (PVAc) in plantation-grown poplar-wood (Populus deltoides) on a few important physical properties, such as density, water absorption, swelling (tangential and volumetric) and surface hardness, were evaluated. Real-time tangential swelling, swelling rates and anti-swelling efficiency of the nano-wood composites were also determined using a customized linear voltage displacement transducer (LVDT)-based swell-o-meter. The dynamic light scattering technique was used to evaluate the dispersion stability and average particle size of the nano-SiO2 fortified polyvinyl acetate before impregnating in wood. The changes in the microstructure, crystallinity, and chemical interactions of nanoparticles, resin and wood elements that occurred in nano-wood composites were studied using scanning electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy techniques. Wood impregnated with 3% nano-SiO2 fortified 20% polyvinyl acetate exhibited the lowest tangential swelling after 2 h of water immersion, while the highest anti-swelling efficiency after saturation was achieved with 3% nano-SiO2 fortified 15% polyvinyl acetate. Mechanical test results also indicated improvement in the end- and side-surface hardness of the wood impregnated with 3–5% nano-SiO2-fortified 20% PVAc. This study provides valuable insights into the potential of using fast-grown low-density poplar-wood impregnated with nano-SiO2 fortified PVAc for various value-added interior applications.