Effects of surface modification with Glutaraldehyde/Nanoclay/Styrene on Poplar Wood Performance

Limited application of fast-growing species due to dimensional changes and low mechanical strength can be expand by modification methods. In this study, the effect of surface modification with aldehydes/nanoparticles/polymer on chemo/physico/mechanical properties of poplar ( Populus Spp .) wood was investigated. For this purpose, specimens were modified with 20% Glutaraldehyde (GA) solution, without and with nano clay (NC) (in 1% and 2%), and subsequently with styrene (St) for combined modification. According to Fourier-transform infrared (FTIR) spectroscopy results, changes of chemical structure confirmed the reaction of GA with wood. Scanning electron microscopy (SEM) images showed reducing of vessels pit aperture size by GA modification and forming a layer of St on the internal surface of lumens, which resulted in less hygroscopicity for modified specimens. The highest dimensional stability was calculated for GA/St and GA/NC/St modified specimens. GA modification enhanced the photostability of wood exposed to accelerated weathering, and this feature was intensified with adding NC. GA modification increased surface roughness and subsequently contact angle of specimens, which was more obvious by adding NC. GA significantly improved the hardness of specimens, and the highest modulus of bending was measured for GA/St modified wood. Finally, it could be concluded that GA/NC/styrene modification is a promising method for enhancing dimensional stability and weathering resistance of poplar wood, but for efficient strengthening of GA modified wood, styrene impregnation under pressure is suggested.