Applicational properties of reinforced plywood with nanomaterials and kenaf fiber

Abstract

Kenaf fibers were added as a reinforcement between wood veneers of poplar (Populus deltoides) bonded with urea–formaldehyde (UF) resin to improve the applicational properties of standard three-layered plywood. Additionally, the influence of two different nanomaterials (nanocellulose and nanosilica)-modified UF resins on the performance of plywood was evaluated. Then, thickness swelling (TS), water absorption (WA), shear strength, and flexural properties were examined. Results indicated that reinforced composites with kenaf fibers improved the modulus of rupture (MOR) and modulus of elasticity (MOE) in both directions. In addition, physical properties, such as TS and WA after 24 h, improved in the reinforced plywood with kenaf and use of nanosilica (KNS) as a filler. The results of the mechanical properties were better than blanks. The treated adhesive, with nanocellulose and nanosilica revealed similar mechanical behaviors. The shear strength of plywood in KNC specimens showed the best result (increased 64.6% compared to blank) and MOR for both the parallel and perpendicular directions to the grain of the surface layers for KNS (105% and 158%, respectively), and MOE for KNS (92.9% and 152%, respectively) compared to the blank.