COMPOSITES FROM BENZYLATED WOOD AND POLYSTYRENES - THEIR PROCESSABILITY AND VISCOELASTIC PROPERTIES

Utilization and conservation of raw materials are two of the main thrusts of our research. Several plasticized woods have been prepared from sawdust in our laboratory. They possess unique thermal, mechanical, and viscoelastic properties. In this study, benzylated wood was used to blend with polystyrene to prepare a wood/plastic composite. Its dynamic processability and viscoelastic properties were evaluated. The mixtures with different blending ratios (benzylated wood/polystyrene) were prepared by mixing them in an intensive mixing device. The specific energy required to do the processing work decreased with the increase of benzylated wood in the composite. The mixture can be molded or extruded easily. The study of the viscoelasticity of the compression-molded composite products using a dynamic mechanical thermal analyzer (DMTA) revealed, regardless of the mixing ratios, a single damping peak (tan delta). This suggested good compatibility between the two polymers. The glass transition temperature and the storage modulus of these composites decreased as the amount of benzylated wood increased. A composite with comparable mechanical properties of polystyrene was obtained from those composites with mixing ratios (benzylated wood/polystyrene) ranging from 0.4 to 0.6. (C) 1993 John Wiley & Sons, Inc.