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Poly(ether ester)s (PEEs) represent a promising class of segmented co-polymers, nevertheless the synthesis of PEEs based on renewable 2,5-furandicarboxylic acid (FDCA) is still scarce. In this context, a series of poly(1,4-butylene 2,5-furandicarboxylate)-co-poly(poly(propylene oxide) 2,5-furandicarboxylate) co-polyesters with different composition of stiff poly(1,4-butylene 2,5-furandicarboxylate) (PBF) and soft poly(poly(propylene oxide) 2,5-furandicarboxylate) (PPOF) moieties were synthesized, via a two-step bulk polytransesterification reaction. The molar ratio of PBF/PPOF incorporated was varied (10 to 50 mol%) in order to prepare several novel materials with tuned properties. The materials were characterised in detail through several techniques, namely ATR FTIR, 1H and 13C NMR, TGA, DSC, DMTA and XRD. Their hydrolytic and enzymatic degradation evaluation was also assessed. These new co-polymers showed either a semi-crystalline nature when higher PBF/PPOF ratios were used, and for approximately equal amounts of PBF and PPOF an amorphous co-polyester was obtained instead.

Polyesters made from 2,5-furandicarboxylic acid (FDCA) have been in the spotlight due to their renewable origins, together with the promising thermal, mechanical, and/or barrier properties. Following the same trend, (nano)composite materials based on FDCA could also generate similar interest, especially because novel materials with enhanced or refined properties could be obtained. This paper presents a case study on the use of furanoate-based polyesters and bacterial cellulose to prepare nanocomposites, namely acetylated bacterial cellulose/poly(butylene 2,5-furandicarboxylate) and acetylated bacterial cellulose/poly(butylene 2,5-furandicarboxylate)-co-(butylene diglycolate)s. The balance between flexibility, prompted by the furanoate-diglycolate polymeric matrix, and the high strength prompted by the bacterial cellulose fibres, enabled the preparation of a wide range of new nanocomposite materials. The new nanocomposites had a glass transition between &minus, 25&ndash, 46 &deg, C and a melting temperature of 61&ndash, 174 &deg, C, and they were thermally stable up to 239&ndash, 324 &deg, C. Furthermore, these materials were highly reinforced materials with an enhanced Young&rsquo, s modulus (up to 1239 MPa) compared to their neat copolyester counterparts. This was associated with both the reinforcing action of the cellulose fibres and the degree of crystallinity of the nanocomposites. In terms of elongation at break, the nanocomposites prepared from copolyesters with higher amounts of diglycolate moieties displayed higher elongations due to the soft nature of these segments.

2,5-Furandicarboxylic acid is a promising renewable-based monomer essentially used in polymer synthesis to prepare renewable-based counterparts to petrochemical polyesters. In general, they are entirely based on renewable resources and have a myriad of very interesting thermal and mechanical properties; however, this study is the first to tackle their (bio) degradability, a worldwide-demanded property. To address this demand, an entirely new generation of furandicarboxylate-derived copolyesters, based on both poly(ethylene 2,5-furandicarboxylate) (PEF) and poly(lactic acid) (PLA), is developed for the first time. These copolyesters are characterized by several techniques, including attenuated total reflectance-Fourier transform IR (ATR-FTIR), H-1, and C-13 NMR spectroscopy, thermogravimetric analysis (TGA), DSC, and X-ray diffraction (XRD), and their degradability behavior is evaluated by water-absorption studies and hydrolytic degradation. They are essentially stiff amorphous polymers possessing high T(g)s, e.g., ca. 69 degrees C for 29% of lactyl units. Importantly, the data show also that they have improved degradability when compared with the PEF homopolyester counterpart.

Motivated by the general concern about sustainability and environmental issues, an intense search for renewable-based polymers has grown exponentially in recent years. This search definitely spotlighted polyesters derived from 2,5-furandicarboxylic acid, among other polymers, as some of the most promising, especially due to the resemblance of this renewable monomer to the well-known petroleum-based terephthalic acid, as well as owing to the possibility of preparing innovative materials. The huge number of recent papers and patents about this family of polymers explore aspects as diverse as synthesis with other renewable-based monomers, leading to the preparation of materials with enhanced thermo-mechanical, biodegradability and liquid crystalline properties, among other features. Additional aspects pursued in such studies are innovation in the synthetic approaches or their optimisation, as well as the development of applications for everyday-life objects for example packaging materials, especially bottles, textiles, coating, and toners, among many other uses. Despite this intense activity, little has been reviewed recently about this unique family of polyesters or derived polymers, as the only reviews on the subject date back to the last century. In this perspective, the present review aims at contributing to filling this literature gap, covering recent aspects related with challenges in developing polyesters, polyamides, or other polymers from 2,5-furandicarboxylic acid and their precursors. Emphasis is placed on monomer synthesis, polymerisation reactions, catalysts and applications.

The use of renewable feedstocks in foam technology has created a worldwide demand for more sustainable materials. Castor oil is a vegetable oil, composed mainly of triricinoglycerol, a natural polyol, suitable for polyurethane foam production. In this study, castor oil and variable amounts of microcrystalline cellulose (MCC) fibers were used in a straightforward one-pot synthesis approach for the preparation of novel biofoams. The ensuing biofoams were characterized by several techniques, including attenuated total reflectance Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetric analysis, and their mechanical performance was evaluated by compression mechanical testing and by dynamic mechanical thermal analysis. They were (semi-) flexible, with a cell-like morphology and reinforced toughness due to the use of MCC. They had a Young's modulus varying between 0.188 and 1.06 MPa depending on the amount of MCC used and were thermally stable up to 267 A degrees C. The properties of these novel biofoams enable them to be strong candidates for use as tough, energy-absorbing foams, advantageously prepared using renewable-based resources.

The search for new polymers from renewable origin is a sparkling field in polymer chemistry, especially those having promising properties, for example, in terms of their thermal performance. In this vein, in this study, an original renewable 2,5-furandicarboxylic acid-based cycloaliphatic homopolyester, poly(1,4-cyclohexylene 2,5-furandicarboxylate) (PCdF), is synthesized from dimethyl-2,5-furandicarboxylate and 1,4-cyclohexanediol. Poly(1,4-cyclohexanedimethylene 2,5-furandicarboxylate) is also prepared for comparison purposes, since it is the direct renewable substitute of poly(1,4-cyclohexanedimethylene terephthalate) and they are structurally related. The resulting homopolyesters are characterized in detail by using attenuated total reflectance Fourier transform infrared, 1H, 13C and 2D NMR, X-ray and elemental analysis, and thermal properties are assessed by thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical thermal analysis. PCdF shows to have a semicrystalline character, exhibiting an extremely high glass transition temperature around 175 °C. Moreover, this polyester also shows to be a high thermally stable material with a degradation temperature of 380.0 °C.

A straightforward partial substitution of non-renewable poly(ethylene terephthalate) by renewable homologous poly(ethylene furandicarboxylate) was successfully done by random copolymerisation of bis(2-hydroxyethyl) terephthalate and bis(hydroxyethyl)-2,5-furandicarboxylate. Different stoichiometric amounts of these monomers were used and the ensuing copolyesters were characterised in detail by several physical chemistry, thermal and mechanical techniques. All copolyesters have the expected chemical structure incorporating both aromatic and furanic units in different amounts accordingly to the stoichiometric feed-ratio. In particular the copolyester having 20% of furan units (PET-ran-PEF 4/1) have similar properties to those of PET homopolyester, despite some minor differences, being a semi-crystalline copolyester with similar glass transition and melting temperatures to those of PET. Also, the mechanical performance of this PET-ran-PEF 4/1 copolyester was in accordance with the PET operating temperature range, tan delta and modulus. (C) 2012 Elsevier Ltd. All rights reserved.

Correction for ‘Biobased polyesters and other polymers from 2,5-furandicarboxylic acid: a tribute to furan excellency’ by Andreia F. Sousa et al., Polym. Chem., 2015, DOI: 10.1039/c5py00686d.