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The aim of this work was to use waste tire rubber (WTR) in the middle layer of hybrid plywood materials. The effects of four variable parameters, namely, WTR contents (430 and 720 g), resin contents (120 and 160 g/m2), hot pressing (single‐stage and two‐stage), and arrangements of veneer layers on the mechanical, physical, and acoustical properties, were studied. Beech (Fagus orientalis) and alder (Alnus glutinosa) veneers having 1.8‐mm thickness were used in the production of hybrid plywood panels. Rubber layers of 3‐ and 5‐mm thickness were used in the middle layer of plywood samples. To produce plywood panels, single‐stage and two‐stage hot‐pressing processes were used. Bonding of wood layers was performed using 120 and 160 g/m2 urea‐formaldehyde resins, and to form the rubber layers and bond them to wood layers, methylene diisocyanate resin (150 g/m2) was used. Overall trend showed that with the increase in rubber content, the physical properties (water absorption, thickness swelling, and sound absorption) of the manufactured panels were improved, while the mechanical properties (modulus of rapture, modulus of elasticity, and impact strength) of the panels were reduced. Both physical and mechanical performances of plywood panels were improved with increase in resin content. An increase in the WTR content in plywood improved the composite's acoustical property. The production process of the wood/rubber plywood did not significantly affect their properties. The order of improvement in the physical properties of the panels is rubber content > resin content > arrangement of layers > pressing process. Copyright © 2015 John Wiley & Sons, Ltd.

This article reports on the use of carbon fiber (CF) and waste rubber (WR) as reinforcing agents for plywood. The aim of this study was to determine the effects of three variable parameters: CF content, WR content, and CF length, on the mechanical and physical properties of the plywood. The properties evaluated were mechanical properties in terms of modulus of rupture (MOR), modulus of elasticity (MOE), and impact strength (IS), and physical properties including water absorption (WA) and thickness swelling (TS). Beech (Fagus orientalis) veneers having 1.8-mm thickness were used in the production of 7-ply plywoods. The CF and WR layers were used in the middle (core) layer of plywood samples. Bonding of the wood layers was done using urea-formaldehyde resin (160 g/m 2 ), and to form the CF and WR layers and bond them to wood veneers, methylene diphenyl isocyanate resin (150 g/m 2 ) were used. Based on the results, the CF was found to have significant effect on the mechanical properties at 99% confidence level. In addition, both the mechanical and physical performances of plywoods improved with increase in the CF content and length. At a certain amount of the CF, the panels with longer (18 cm) CF showed superior mechanical properties. As it expected, the MOR values considerably reduced with the addition of WR, while the MOE, IS, WA, and TS of the specimens improved when compared with the control. The IS of the samples increased as much as 32.5% with the addition of 30 wt% of the WR. POLYM. COMPOS., 39:675-680, 2018.