Improving core bond strength and dimensional stability of particleboard using polymer powder in core layer

Abstract

Low density polyethylene powder (LDPE) was used as polymer binder in the core layer of three layer particleboard. In the first phase, six levels of the LOPE powder (5-30 wt.%) based on the composition by weight, were mixed with the core particles with 8 wt.% urea-formaldehyde (UF) resin. In the second phase, the LDPE powder content was kept constant at 10 wt.% in all treatments and the UF resin content applied to the core layer was decreased gradually from 8 to 4 wt.%. Thickness swelling and water absorption of the particleboards significantly decreased with increasing the LOPE content in the core layer. Similarly, incorporation of the LOPE powder into the core layer of the particleboard greatly improved internal bond strength. The flexural properties of the particleboards, the modulus of rupture (MOR) and modulus of elasticity (MOE), were positively affected by increasing LDPE content up to 10 wt.% but the further increment of the LOPE decreased the MOR and MOE. The UF resin content can be reduced in the core layer of the particleboard as a function of increasing the LOPE powder. (C) 2012 Elsevier Ltd. All rights reserved.