105 pubblicazioni classificate nel seguente modo:

Revalorization of Posidonia Oceanica as reinforcements in polyethylene/maleic anhydride grafted polyethylene composites
JOURNAL OF RENEWABLE MATERIALS
Autore/i: Puglia, Debora; Petrucci, Roberto; Fortunati, Elena; Luzi, Francesca; Kenny, Jose Maria; Torre, Luigi
Classificazione: 1 Contributo su Rivista
Abstract: Posidonia Oceanica waste was used as reinforcement in a polyethylene matrix and the obtained composites were characterised by a tensile test and morphological analysis. The fi brous material derived from P. Oceanica wastes was characterised by morphological, thermal and chemical analysis, and a subsequent treatment with sodium hydroxide (NaOH) at different weight content (2, 5 and 10 wt%) was considered as an optimised method for surface modifi cation of pristine fi bres (PO). The TGA analysis and morphological investigation of the treated fi bres selected the 5 wt% of NaOH as the best treatment. Matrix compatibilisation with maleic anhydride grafted polyethylene was also considered and the effect on both grafting procedure and alkali treatment was studied for composites containing 20 wt% of fi bres. The results confi rmed that it is possible to aim for a revalorisation of coastal algae and seaweed wastes as raw material for polyolefi n matrix composites, even without applying a strong chemical treatment to the waste
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/296516

Optimized extraction of cellulose nanocrystals from pristine and carded hemp fibres
INDUSTRIAL CROPS AND PRODUCTS
Autore/i: Luzi, Francesca; Fortunati, Elena; Puglia, Debora; M., Lavorgna; C., Santulli; Kenny, Jose Maria; Torre, Luigi
Classificazione: 1 Contributo su Rivista
Abstract: The extraction of cellulose nanocrystals (CNC) from Carmagnola hemp fibres has been carried out. Before CNC extraction, the effectiveness of two pre-treatment methods, an alkaline chemical and a pectinase enzymatic treatment, applied on the pristine and carded hemp fibres, were compared. Carding allowed removal of most impurities from the fibres, while it had only a modest effect on their structure. After chemical treatment, hemicellulose was removed, more efficiently in carded hemp, and X-ray diffraction suggests an increase in the size of cellulose crystallites. Carded hemp fibres, after interaction with pectinase, show the total decomposition of pectin and hemicellulose. On the basis of these results, carded hemp was selected as start material for CNC extraction and the acid hydrolysis for CNC synthesis was applied on carded hemp after both chemical and enzymatic procedures. The yield of the different hydrolysis methods remains approximately at the same level (around 19%): on the other side, a carding procedure, combined with an alkaline treatment to hemp fibres, represents an optimized process for CNC extraction by acid hydrolysis.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/296475

Investigation of thermo-mechanical, chemical and degradative properties of PLA-limonene films reinforced with cellulose nanocrystals extracted from Phormium tenax leaves
EUROPEAN POLYMER JOURNAL
Autore/i: Fortunati, Elena; Luzi, Francesca; Puglia, Debora; F., Dominici; C., Santulli; Kenny, Jose Maria; Torre, Luigi
Classificazione: 1 Contributo su Rivista
Abstract: Poly(lactic acid) (PLA) bio-nanocomposite films modified with limonene as plasticizer and reinforced with cellulose nanocrystals (CNC) extracted from agro-waste, such as Phormium tenax leaves, have been prepared by using a twin-screw microextruder and characterized. The extraction of cellulose was carried out by chemical treatment followed by sulphuric acid hydrolysis process. Binary and ternary films containing the plasticizer (20 wt.%) and/or the CNC (1 and 3 wt.%) were produced and characterized in terms of morphological, thermal, mechanical and wettability properties. The effect of CNC content and the combination with the specific plasticizer on the structural properties of PLA films were also investigated. The addition of limonene into the PLA matrix reduces, as expected, the glass transition temperature of the films, and affects the mechanical properties of the films, increasing the plastic response of PLA. Disintegration study was also carried out under simulated composting conditions in a laboratory-scale test at 58 °C, 50% of humidity and in aerobic conditions, demonstrating that the presence of both plasticizer and CNC can alter the degradation rate of developed PLA-based formulations. The successful production of PLA biodegradable nanocomposites incorporating cellulosic material from agro-waste suggested the possible application of these new bio-nanocomposites for active food packaging.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/296534

Ternary PVA nanocomposites containing cellulose nanocrystals from different sources and silver particles: Part II
CARBOHYDRATE POLYMERS
Autore/i: Fortunati, Elena; Luzi, Francesca; Puglia, Debora; Terenzi, Andrea; M., Vercellino; L., Visai; C., Santulli; Torre, Luigi; Kenny, Jose Maria
Classificazione: 1 Contributo su Rivista
Abstract: Cellulose nanocrystals (CNC) extracted from three different sources, namely flax, phormium, and commercial microcrystalline cellulose (MCC) have been used in a polyvinyl alcohol (PVA) matrix to produce anti-bacterial films using two different amounts of silver nanoparticles (0.1 wt% and 0.5 wt%). In general, CNC confer an effect of reinforcement to PVA film, the best values of stiffness being offered by composites produced using phormium fibres, whilst for strength those produced using flax are slightly superior. This was obtained without inducing any particular modification in transition temperatures and in the thermal degradation patterns. As regards antibacterial properties, systems with CNC from flax proved slightly better than those with CNC from phormium and substantially better than those including commercial MCC. Dynamic mechanical thermal analysis (DMTA) has only been performed on the ternary composite containing 0.1 wt% Ag, which yielded higher values of Young's modulus, and as a whole confirmed the above results.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/296523

Binary PVA bio-nanocomposites containing cellulose nanocrystals extracted from different natural sources: Part I
CARBOHYDRATE POLYMERS
Autore/i: Fortunati, Elena; Puglia, Debora; Luzi, Francesca; C., Santulli; Kenny, Jose Maria; Torre, Luigi
Classificazione: 1 Contributo su Rivista
Abstract: PVA bio-nanocomposites reinforced with cellulose nanocrystals (CNC) extracted from commercial microcrystalline cellulose (MCC) and from two types of natural fibres, Phormium tenax and Flax of the Belinka variety, were produced by solvent casting in water. Morphological, thermal, mechanical and transparency properties were studied while the respective efficiency of the extraction process of CNC from the three sources was evaluated. The effect of CNC types and content on PVA properties and water absorption capacity were also evaluated. Natural fibres offered higher levels of extraction efficiency when compared with MCC hydrolysis yield. Thermal analysis proved that CNC promotes the crystallization of the PVA matrix, while improving its plastic response. It was also clarified that all PVA/CNC systems remain transparent due to CNC dispersion at the nanoscale, while being all saturated after the first 18–24 h of water absorption.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/296485