Effect of processing parameters on mechanical properties of lightweight foam core sandwich panels

Abstract

Sandwich-like lightweight wood-based panels were produced in an integrated one-stage process using resinated wood particles as faces and expandable polystyrene (EPS) as the core layer. Two different press temperatures (130 and 160°C) were applied to reach different foam structures in the core. The results showed that there is a significant correlation between the foam structure and the mechanical properties of the panels. The bending strength of the panels prepared at 130°C was nearly 10% higher compared to the panels prepared at 160°C. A significant lower internal bond (IB) was observed for samples produced at the higher pressing temperature. The specific bending strength and IB fulfilled the calculated requirement values of conventional particleboard. Statistical analyses did not confirm significant differences for face screw withdrawal resistance (SWR) of the panels prepared at the two different pressing temperatures. It was found that the edge SWR for the 160°C pressing temperature is significantly higher than for the 130°C pressing temperature.

Keywords:

• Lightweight
• sandwich
• EPS
• foam
• polystyrene
• wood-based panels

Acknowledgements

Ali Shalbafan acknowledges a doctoral scholarship from “Ministry of Science, Research and Technology of Iran”. The authors would like to thank Dr. R. Lehnen for his valuable comments regarding glass transition temperature and Mrs. T. Potsch for preparing the FESEM micrographs. We gratefully acknowledge Sunpor and BASF for supplying materials.