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ALESSANDRO NANNI

DIPENDENTE ALTRA UNIVERSITA presso: Dipartimento di Ingegneria "Enzo Ferrari"


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Pubblicazioni

2021 - Effect of the wine wastes on the thermal stability, mechanical properties, and biodegradation's rate of poly(3-hydroxybutyrate) [Articolo su rivista]
Nanni, A.; Messori, M.
abstract

In this work, two different wine derived additives, seeds extracts (Sext) and wine lees (WL), have been tested within poly(3-hydroxybutyrate) (PHB) for different purposes. First, the effect of wine seed polyphenolic extracts (Sext) on the PHB thermal stability has been investigated considering the molecular weight decrease (gel permeation chromatography), the impact on the viscosity (mass flow rate), the thermogravimetric analysis (TGA) curves, and the oxidation induction times. Different stabilizers formulations have been tested and the results have been compared with unstabilized PHB. Subsequently, WL have been mixed in different concentration (10, 20, and 40 phr) within PHB by twin-screw extrusion and the obtained biocomposites have been characterized from a thermal (differential scanning calorimetry and TGA) and mechanical (dynamic mechanical analysis and tensile test) points of view exploiting also the micromechanics models of Voigt, Halpin-Tsai and Pukanszky. Finally, biodegradation tests in soil and in marine water have been carried out for each investigated PHB formulation in order to evaluate the effect of Sext and WL on the microbial degradation.


2021 - Functionalization and use of grape stalks as poly(butylene succinate) (PBS) reinforcing fillers [Articolo su rivista]
Nanni, Alessandro; Cancelli, Umberto; Montevecchi, Giuseppe; Masino, Francesca; Messori, Massimo; Antonelli, Andrea
abstract

Grape stalks are a lignocellulosic biomass, which is a very complex material, whose easy and profitable fractionation to obtain its basic components is still not available. Therefore, alternative ways to try and make use of grape stalks are currently being explored. In the present study, the possible use of dried and milled grape stalks as filler in bio-composites was assessed using polybutylene succinate as a basic polymer. The tensile specimens produced using 10% grape stalk powder as it is and functionalized through pre-extrusion acetylation and silylation, and silylation in situ were characterized for their structural, mechanical, thermal, morphological, and color properties. The bio-composites showed to be stiffer than the control polymer, with an increase of Young’s modulus from 616 MPa to 732 MPa in the specimens obtained with acetylated grape stalk powder. This led to a potentially new method to valorize by-products of the wine industry such as grape stalks in order to recover raw materials which could prove useful in the biomaterials and bio-composites sector.


2020 - Thermo-mechanical properties and creep modelling of wine lees filled Polyamide 11 (PA11) and Polybutylene succinate (PBS) bio-composites [Articolo su rivista]
Nanni, A.; Messori, M.
abstract

Solid wine wastes named wine lees (WL) have been mixed in different percentages (10, 20 and 40 phr) within Polyamide 11 (PA11) and Polybutylene Succinate (PBS) by twin-screw extrusion. Reactive extrusion has been also tested using 3-methacryloxypropyltrimethoxysilane tested as coupling agent. The obtained bio-composites have been characterized from a thermal (DSC, TGA, HDT), rheological (MFR), mechanical (tensile test) and thermo-mechanical (DMA, creep test) point of view. Micro-mechanics models of Voigt, Halpin-Tsai and Pukanszky have been fitted on tensile properties data meanwhile the creep behavior has been modeled and described through the models of Burger, Kohlrausch-Williams-Watts and Findley.


2020 - Wine derived additives as poly(butylene succinate) (PBS) natural stabilizers for different degradative environments [Articolo su rivista]
Nanni, A.; Ricci, A.; Versari, A.; Messori, M.
abstract

A grape pomace extract (GPext) and a grape seed extract (T) have been melt mixed within poly(butylene succinate) (PBS) and tested as natural stabilizers. Their effect on the PBS stabilization has been evaluated trough thermo-mechanical degradative tests (reprocessing), thermo-oxidation (oven aging), thermogravimetric analysis (TGA) and biodegradation tests. GPext and T have been deeply analyzed in terms of polyphenolic profile and bioactivity to connect the stabilization's results with the antioxidant's structures. Additive T exhibited the best results, maintaining unaltered the PBS molecular weight both after six reprocessing steps and after 300 h of oven aging and to increase the degradation temperature of more than 20 °C. These encouraging results have been explained by the long-chains polyphenols present within T (medium degree of polymerization of 10.8), by the excellent radical scavenger activity of T (6.0 mM TEAC) and by the low releases of peroxides from T (0.06 µM H2O2).


2019 - Materiale composito formato da un biofiller e da una matrice termoplastica e procedimento per realizzare un articolo con un tale materiale composito [Brevetto]
Nanni, Alessandro; Messori, Massimo
abstract


2019 - Thermal and UV aging of polypropylene stabilized by wine seeds wastes and their extracts [Articolo su rivista]
Nanni, A.; Battegazzore, D.; Frache, A.; Messori, M.
abstract

A commercial tannin wine seed extract powder (T), a seed polyphenol extract (Sext) and virgin wine seeds wastes (Se) have been mixed with polypropylene (PP) and tested as long-term stabilizers. Their stabilizing activity has been compared with that of a synthetic antioxidant commonly used within PP (Irganox 1010). Each sample has been subject to both UV and thermal aging. The PP-based films photo-oxidation has been followed through the C=O formation over the aging time by FT-IR. The PP-based tensile specimens have been oven aged and the mechanical properties loss has been investigated monitoring the variation of the elongation at break. Melt Flow Index (MFI) measures and Different Scanning Calorimetry analysis have been conducted on thermally aged samples. At the same time, wine derived additives have been characterized in terms of total polyphenol content, FT-IR and UV/VIS spectra meanwhile catechin and gallic acid have been quantified by LC-MS. Experimental results have evidenced the ability of all the wine derived additives to withstand both to thermal and UV long-term degradation. In particular, wine seeds extracts exhibit the best results in terms of stabilization (even better than Irganox 1010) without compromising the PP mechanical, thermal, morphological and rheological properties.


2018 - A comparative study of different winemaking by-products derived additives on oxidation stability, mechanical and thermal proprieties of polypropylene [Articolo su rivista]
Nanni, A.; Messori, M.
abstract

Three different solid wine wastes (peels, seeds and stalks) have been mixed with polypropylene (PP) and tested as stabilizers. Their stabilizing activity has been compared with that of a commercial tannin extract powder, rich in polyphenol. Thermogravimetric analysis, Oxidation Induction Time and Oxidation Onset Temperature measurements have been conducted to investigate the thermo-oxidative stability. Tensile tests, Dynamic Mechanical Analysis and Differential Scanning Calorimetry have been conducted on the samples in order to evaluate the effect of the additives also on the thermal and mechanical properties. Scanning Electron Microscopy have been used to assess the adhesion and distribution of the wine-wastes additives within the PP matrix. Experimental results evidence that all three wine-wastes derived additives do not significantly change the mechanical and thermal properties of PP, meanwhile they enhance its thermal stability. Moreover, the expectation to obtain better results with the commercial tannin extract has not been achieved. The obtained results show how wine wastes can be effectively used as polymer stabilizers and represent a valid alternative because of theirs environmental and cost-effects advantages.