Basalt fibre-reinforced high density polyethylene composite development using the twin screw extrusion process

Abstract

Offshore renewable energy can lead the way towards sustainable energy harvesting and support the achievement of the CO2 reduction target by 2030. To achieve this goal it is necessary to decrease the manufacturing and deployment cost of the offshore devices. This paper focusses on the mechanical, chemical and microstructural assessment of a novel high density polyethylene (HDPE) reinforced with short basalt fibres for potential application as a hull material for wave energy devices. The choice of short fibres ensures the new composite can utilise existing low cost manufacturing methods for HDPE structures. In particular this study compares the properties of material with a recycled HDPE matrix with the properties of a material using a virgin HDPE matrix. The mechanical properties achieved by the novel composites exceed an improvement of ~300% in the properties of the monolithic polymer hence indicating the potential of this material, both for recycled and virgin HDPE. Furthermore, exploration in detail of the interaction fibres/matrix indicated the dynamic reaction between coupling agent and polymeric matrix showing the formation of molecular bonding perpendicular to the fibres, hence enhancing a 3D network that further increases the reinforcement abilities of the fibres.