Effect of processing parameters on physical and structural properties of lightweight foam core sandwich panels

Weight reduction is becoming an important topic for the wood-based panels industry. Recent development for foam core particleboard in an integrated process has a great potential to replace heavy conventional particleboards. For further progress of these new types of panels, exploring the physical properties is of high interest. In this study, the effect of two different sets of process parameters (press temperature, pressing and foaming times) on the physical properties and dimensional stability of foam core panels was examined. Panels produced by a lower press temperature (1308 C) have a better surface quality. Thickness swelling of panels in short- (2 h) and long-term (24 h, 14 days) immersion shows different trends due to the different attained foam structures. Small inter cellular voids between the foam cells formed during the in situ foaming process play an important role for the water absorption values, especially in short-term immersion. Different process parameters caused different fusion of the beads in the core layer. With increasing panel density, the dimensional stability is significantly decreased because of the increased wood particles in the face layer. With proper selection of process parameters, foam core panels with higher dimensional stability than conventional particleboards can be produced