Ricerc@Sapienza

Different surface treatments including mercerization, stearic acid and growth of zinc oxide nanorods as well as their combinations were exploited to address their effects on the properties of green composites based on polylactic acid (PLA) and flax fabrics. The resulting fabrics were morphologically (SEM), crystallographically (XRD) and thermally (TGA) characterized, showing no significant changes with respect to the untreated samples. In contrast, tensile and flexural properties of composites produced by compression moulding were significantly influenced.

To improve plant fibres/polymer matrix adhesion, the surface of flax yarns was modified by zinc oxide (ZnO) nanorods, which were synthesized through a hydrothermal treatment. Several parameters were analysed in order to obtain a uniform and homogeneous ZnO interphase, such as the number of seeding cycles, growth times and the replacement of the growth solution.

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

This work investigates the morphology, the thermal, and
mechanical properties of technical fibers extracted from
the Ampelodesmos mauritanicus (Diss) grass using a process
that combines mechanical, mild chemical, and enzymatic
steps. The structure and the thermal stability of Diss
fibers make them suitable as a reinforcing filler in polymer
composites, which was assessed by manufacturing biocomposites
with improved stiffness and a tensile strength
not degraded by Diss fibers when compared to those of a

The aim of this study was to assess the effects of commercially available and relatively inexpensive enzyme preparations based on endo 1,4-β-xylanase, pectinase and xyloglucanase on the thermal (TGA), morphological (SEM), chemical (FT-IR) and mechanical (single yarn tensile tests) properties of flax yarns.

Blends based on high density polyethylene (HDPE) and poly(lactic) acid (PLA) with different ratios of both polymers were produced: a blend with equal amounts of HDPE and PLA, hence 50 wt.% each, proved to be a useful compromise, allowing a high amount of bio-derived charge without this being too detrimental for mechanical properties and considering its possibility to biodegradation behaviour in outdoor application.

Despite the academic interest in using plant fibres as reinforcement in polymer composites to replace glass fibres, the industrial exploitation of resulting composites in semi- or structural applications is still limited. This is mainly due to the poor adhesion at the plant fibre/polymer matrix interface dictated by their surface chemistry and strong hydrophilic behaviour. In the present work, an assessment of the interfacial adhesion at the yarn scale has been carried out. Fragmentation tests have been performed on flax/epoxy and flax/vinylester single yarn composites.

The aim of this work was to study the effect of free surface energy modification of flax fibres by a thermal treatment on the mechanical behaviour of bio-based composites. It has been proved that this modification enhances the wettability of flax fibres by liquid epoxy resin and results in a lower porosity amount in composites. Tests to evaluate mechanical properties of elementary fibres, yarns and composites have been performed.

In an attempt to improve mechanical properties of basalt fibre/epoxy composites, the present work provides a