CNR ExploRA

Articolo in rivista, 2020, ENG, 10.1021/acs.biomac.0c00039

Polymorphism and Multiple Melting Behavior of Bio-Based Poly(propylene 2,5-furandicarboxylate)

Righetti M.C.; Marchese P.; Vannini M.; Celli A.; Lorenzetti C.; Cavallo D.; Ocando C.; Muller A.J.; Androsch R.

CNR-IPCF, National Research Council-Institute for Chemical and Physical Processes, Via Moruzzi 1, Pisa, 56124, CNR-IPCF, National Research Council-Institute for Chemical and Physical Processes, Via Moruzzi 1, 56124 Pisa, Italy, , , Italy; CNR-IPCF, National Research Council-Institute for Chemical and Physical Processes, Via Moruzzi 1, Pisa, 56124, CNR-IPCF, National Research Council-Institute for Chemical and Physical Processes, Via Moruzzi 1, 56124 Pisa, Italy, , , Italy; Department of Civil Chemical, Environmental, and Materials, University of Bologna, Via Terracini 38, Bologna, 40131, Department of Civil, Chemical, Environmental, and Materials, University of Bologna, Via Terracini 38, 40131 Bologna, Italy, , Italy; Tetra Pak Packaging Solution Ab, Ruben Rausing Gata, Lund, SE-221 86, Tetra Pak Packaging Solution AB, Ruben Rausing Gata, SE-221 86 Lund, Sweden, , Sweden; Department of Chemistry and Industrial Chemistry, University of Genoa, Via Dodecaneso 31, Genova, 16146, Department of Chemistry and Industrial Chemistry, University of Genoa, Via Dodecaneso 31, 16146 Genova, Italy, , Italy; Polymat and Polymer Science and Technology Department, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizábal 3, Donostia-San Sebastián, 20018, POLYMAT and Polymer Science and Technology Department, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizábal 3, 20018 Donostia-San Sebastián, Spain, , , Spain; Polymat and Polymer Science and Technology Department, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizábal 3, Donostia-San Sebastián, 20018, POLYMAT and Polymer Science and Technology Department, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizábal 3, 20018 Donostia-San Sebastián, Spain, , , Spain; Ikerbasque, Basque Foundation for Science, Bilbao, 48013, IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain, , Spain; Interdisciplinary Center for Transfer-oriented Research in Natural Sciences, Martin Luther University Halle-Wittenberg, Halle/Saale, 06099, Interdisciplinary Center for Transfer-oriented Research in Natural Sciences, Martin Luther University Halle-Wittenberg, 06099 Halle/Saale, Germany, , Germany

Furandicarboxylate-based polyesters are considered an interesting class of bio-based polymers due to their improved properties with respect to the petrol-based terephthalate homologs. An in-depth analysis of the crystal structure of poly(propylene 2,5-furandicarboxylate) (PPF), after maximum possible removal of the catalyst, was carried out. The study disclosed that purified PPF presents two different crystalline phases after crystallization from the melt. Crystallizations at temperatures lower than 120 °C lead to growth of a single crystal form (?-form), whereas two different crystal forms (? and ?) were found to coexist at higher Tcs. This behavior is opposite to that previously observed for unpurified PPF. The possibility that the catalyst nucleates the ?-phase, which therefore becomes the kinetically favored modification at low crystallization temperatures in the presence of a higher amount of catalyst residue, has been considered as a feasible explanation. Two concomitantly different spherulitic morphologies were observed and connected to the ?- A nd ?-phase, respectively. The association between polymorphism and melting behavior was studied. The origin of the peaks that compose the multiple melting endotherm recorded at conventional heating rates was determined by combined wide-angle X-ray scattering, differential scanning calorimetry, fast scanning chip calorimetry, and polarized light optical microscopy measurements. The higher thermal stability of the ?-crystals in comparison with the ?-form was thus demonstrated.

Biomacromolecules 21 , pp. 2622–2634