Evaluation of the Gluing Process of Maritime Pine Wood Veneers for Application in Overmolding

Abstract

The gluing process of thin wood veneers is a crucial step for the use of wood as a finishing layer to injected plastic parts, through the overmolding process. Based on the published studies on pine wood gluing for the production of laminated veneer lumber (LVL) and plywood panels, a phenol–resorcinol–formaldehyde (PRF) glue was selected for the assessment of the gluing process of Portuguese maritime pine wood. The gluing of the wood veneers was carried out in a hot pressing machine, equipped with electronic temperature control, under 800 kPa of applied pressure, and a glue mix spread rate of 350 g/m2. The influence of the gluing parameters (gluing temperature and pressing time) on dimensional and physical properties of the glued wood veneers was evaluated. Additionally, experimental determination of bending strength and modulus of elasticity of the glued wood veneers were carried out through three-point bending tests. According to the results obtained, and despite the uncertainties that need to be addressed, it seems feasible to consistently glue maritime pine wood veneers to use them as a top layer in the overmolding process of plastics.