The effect of silver and copper nanoparticles as resin fillers on less-studied properties of UF-based particleboards

Abstract

ABSTRACT The aim of this study was to investigate the effect of using silver and copper nano-suspensions in mixture with resin, upon screw withdrawal capacity (in face and edge directions) and hardness (at different depths of penetration) of particleboards. An aqueous-suspension of 200 ppm silver and copper was mixed with urea-formaldehyde resin at two levels of 100 and 150 mL/kg dry weight wood particles. The size range of at least 70% of nano-particles was 20–90 nm. The results revealed a significant increase in screw withdrawal capacity and hardness by adding the nanometals to composite mats. The increased properties were partially attributed to an improvement in heat transfer in mats that facilitated the curing of resin. Moreover, theoretical simulations based on density functional theory (DFT) clearly demonstrated high adsorption energy of silver and copper atoms on cellulose and hemicellulose polymers; this contributed to a formation of additional bonds throughout the composite matrix, which in turns improved the board properties.