1. Statistical modeling and optimization of the drawing process of bioderived polylactide/poly(dodecylene furanoate) wet-spun fibersDaniele Rigotti, Giulia Fredi, Davide Perin, Dimitrios Bikiaris, Alessandro Pegoretti, Andrea Dorigato, 2022, izvirni znanstveni članek Opis: Drawing is a well-established method to improve the mechanical properties of wet-spun
fibers, as it orients the polymer chains, increases the chain density, and homogenizes the microstructure. This work aims to investigate how drawing variables, such as the draw ratio, drawing speed,
and temperature affect the elastic modulus (E) and the strain at break (εB) of biobased wet-spun fibers
constituted by neat polylactic acid (PLA) and a PLA/poly(dodecamethylene 2,5-furandicarboxylate)
(PDoF) (80/20 wt/wt) blend. Drawing experiments were conducted with a design of experiment
(DOE) approach following a 24
full factorial design. The results of the quasi-static tensile tests on
the drawn fibers, analyzed by the analysis of variance (ANOVA) and modeled through the response
surface methodology (RSM), highlight that the presence of PDoF significantly lowers E, which instead
is maximized if the temperature and draw ratio are both low. On the other hand, εB is enhanced
when the drawing is performed at a high temperature. Finally, a genetic algorithm was implemented
to find the optimal combination of drawing parameters that maximize both E and εB. The resulting
Pareto curve highlights that the temperature influences the mechanical results only for neat PLA
fibers, as the stiffness increases by drawing at lower temperatures, while optimal Pareto points for
PLA/PDoF fibers are mainly determined by the draw ratio and the draw rate.
Ključne besede: fibers, poly(lactic acid), furanoate polyesters, drawing, response surface methodology, genetic algorithms
Objavljeno v DKUM: 24.03.2025; Ogledov: 0; Prenosov: 2
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2. Improving the Thermomechanical Properties of Poly(lactic acid) via Reduced Graphene Oxide and Bioderived Poly(decamethylene 2,5-furandicarboxylate)Giulia Fredi, Mahdi Karimi Jafari, Andrea Dorigato, Dimitrios Bikiaris, Alessandro Pegoretti, 2022, izvirni znanstveni članek Opis: Polylactide (PLA) is the most widely used biopolymer, but its poor ductility and scarce
gas barrier properties limit its applications in the packaging field. In this work, for the first time,
the properties of PLA solvent-cast films are improved by the addition of a second biopolymer, i.e.,
poly(decamethylene 2,5-furandicarboxylate) (PDeF), added in a weight fraction of 10 wt%, and a
carbon-based nanofiller, i.e., reduced graphene oxide (rGO), added in concentrations of 0.25–2 phr.
PLA and PDeF are immiscible, as evidenced by scanning electron microscopy (SEM) and Fouriertransform infrared (FTIR) spectroscopy, with PDeF spheroidal domains showing poor adhesion to
PLA. The addition of 0.25 phr of rGO, which preferentially segregates in the PDeF domains, makes
them smaller and considerably rougher and improves the interfacial interaction. Differential scanning
calorimetry (DSC) confirms the immiscibility of the two polymer phases and highlights that rGO
enhances the crystallinity of both polymer phases (especially of PDeF). Thermogravimetric analysis
(TGA) highlights the positive impact of rGO and PDeF on the thermal degradation resistance of PLA.
Quasi-static tensile tests evidence that adding 10 wt% of PDeF and a small fraction of rGO (0.25 phr)
to PLA considerably enhances the strain at break, which raises from 5.3% of neat PLA to 10.0%
by adding 10 wt% of PDeF, up to 75.8% by adding also 0.25 phr of rGO, thereby highlighting the
compatibilizing role of rGO on this blend. On the other hand, a further increase in rGO concentration
decreases the strain at break due to agglomeration but enhances the mechanical stiffness and strength
up to an rGO concentration of 1 phr. Overall, these results highlight the positive and synergistic
contribution of PDeF and rGO in enhancing the thermomechanical properties of PLA, and the
resulting nanocomposites are promising for packaging applications.
Ključne besede: nanocomposites, reduced graphene oxide, poly(decamethylene 2, 5-furandicarboxylate), furanoate polyesters, polylactic acid, compatibilization
Objavljeno v DKUM: 20.03.2025; Ogledov: 0; Prenosov: 1
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3. Recent trends in the synthesis of monomers for furanoate polyesters and their nanocomposites’ fabrication as a sustainable packaging materialJohan Stanley, Lidija Fras Zemljič, Dimitra A. Lambropoulou, Dimitrios Bikiaris, 2024, izvirni znanstveni članek Opis: Furanoate polyesters are an extremely promising new class of materials for packaging applications, particularly furanoate-based nanocomposites, which have gained a high interest level in research and development in both academia and industries. The monomers utilised for the synthesis of furanoate-based polyesters were derived from lignocellulosic biomass, which is essential for both eco-friendliness and sustainability. Also, these polyesters have a lower carbon footprint compared to fossil-based plastics, contributing to greenhouse gas reduction. The furanoate-based nanocomposites exhibit enhanced performance characteristics, such as high thermal stability, excellent mechanical strength, superior barrier resistance, and good bacteriostatic rate, making them suitable for a wide range of industrial applications, especially for food-packaging applications. This paper reviews the recent trends in the synthesis routes of monomers, such as the various catalytic activities involved in the oxidation of 5(hydroxymethyl)furfural (HMF) into 2,5-furandicarboxylic acid (FDCA) and its ester, dimethyl furan-2,5-dicarboxylate (DMFD). In addition, this review explores the fabrication of different furanoate-based nanocomposites prepared by in situ polymerization, by melt mixing or solvent evaporation methods, and by using different types of nanoparticles to enhance the overall material properties of the resulting nanocomposites. Emphasis was given to presenting the effect of these nanoparticles on the furanoate polyester’s properties.
Ključne besede: 2, 5-furandicarboxylic acid, dimethyl furan-2, 5-dicarboxylat, furanoate polyesters, furanoate nanocomposites, thermal properties, mechanical properties, antibacterial properties, sustainable packaging
Objavljeno v DKUM: 10.03.2025; Ogledov: 0; Prenosov: 5
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