Ricerc@Sapienza

The disposal of fibre reinforced composite materials is a problem widely debated in the literature. This work explores the ability to restore the mechanical properties of thermally conditioned basalt fibres through chemical treatments. Inorganic acid (HF) and alkaline (NaOH) treatments proved to be effective in regenerating the mechanical strength of recycled basalt fibres, with up to 94% recovery of the strength on treatment with NaOH.

Despite the advantages offered by natural fibre-based thermoplastic composites in terms of environmental impact and cost, their mechanical performance is generally lower than that of synthetic counterparts. Hybridisation with mineral fibres (basalt) can broaden the industrial applications of natural fibre reinforced composites. The present study focused on the performance of injection-moulded short basalt fibre, hemp fibre and hemp/basalt fibre hybrid high density polyethylene (HDPE) composites.

The Achilles heel of thermoplastic natural fibre composites is their limited durability. The
environmental degradation of the mechanical properties of hemp and hemp/basalt hybridreinforced
high-density polyethylene (HDPE) composites has been investigated with a special focus
on the effects of water ageing and accelerated ageing, including hygrothermal and UV radiation.
Modification of the matrix was carried out using a maleic anhydride high-density polyethylene
copolymer (MAPE) as a compatibilizer. Hybridization of hemp fibres with basalt fibres and the

The presence of a secondary phase between the fibres and the matrix has proved to be a good approach for interphase tailoring for enhanced load transfer. In this regard, an optimization of the low-temperature hydrothermal growth process of ZnO-nanorods on different basalt substrates as a function of different growth times was performed. Scanning electron microscope and X-ray diffraction analysis revealed the best results in terms of homogeneity and uniformity of the ZnO nanostructures for the longest growth time, i.e., 5 h for basalt fabrics and 120 minutes for single basalt fibres.

INTRODUCTION