Effect of accelerated ageing on the mechanical behaviour of basalt/hemp hybrid composites

The remarkable concerns related to environmental pollution have triggered a lot of studies aimed at decreasing the environmental impact of polymer composites. A possible way to achieve this goal is the replacement of glass fibres with natural ones. In particular, lignocellulosic fibres are of considerable interest because they are renewable resources and are characterized by low cost, low density, thermal and acoustic insulation, biodegradability and recyclability. Despite these favourable attributes, cellulosic fibre reinforced composites do not provide mechanical properties comparable with those of glass fibre composites and, most importantly, their susceptibility to moisture absorption can significantly reduce their durability. A solution is the hybridization of natural fibres with synthetic ones characterized by superior ageing resistance. This approach has been widely exploited in literature mainly with glass fibres [1]. In this paper, the use of mineral fibres, namely basalt fibres, is suggested as an effective way to enhance the durability of thermoplastic based composites reinforced with hemp fibres, with a view to broadening the applications of natural fibre composites. Basalt fibres are natural fibres with mechanical, thermal and chemical properties comparable, if not superior, to those of glass fibres [2]. The effects of basalt hybridization on mechanical and thermal response of hemp/HDPE composites have been investigated in terms of resistance to accelerated ageing tests for periods up to 56 days.