Development of recycled polymer composites for structural applications

This paper is concerned with the formulation of composite materials for structural or semistructural applications using thermoplastic polymer waste. The mechanical and thermal properties of a proprietary blend of recycled polymers with a range of different fillers were investigated. The effect varied with the aspect ratio of the filler and the mode of loading. Spherical calcium carbonate gave a marginal improvement in modulus. Plate-like mica produced a significant increase in modulus without reduction in strength. Glass fibres caused a significant increase in modulus and strength while decreasing the linear coefficient of thermal expansion. Hybrid systems containing glass fibre and a lower aspect ratio filler were also investigated to obtain a material system which combines high properties and reasonably low cost. It was found that addition of small quantities of mica to glass fibre reinforced blends exhibited a significant synergy in tensile strength and modulus.