Two homopolyesters and a series of novel random copolyesters were synthesized from two bio-based diacid esters, dimethyl 2,5-furandicarboxylate, a well-known renewable monomer, and dimethyl 2,2′-bifuran-5,5′-dicarboxylate, a more uncommon diacid based on biochemical furfural. Compared to homopolyesters poly­(butylene furanoate) (PBF) and poly­(butylene bifuranoate) (PBBf), their random copolyesters differed dramatically in that their melting temperatures were either lowered significantly or they showed no crystallinity at all. However, the thermal stabilities of the homopolyesters and the copolyesters were comparable. Based on tensile tests from amorphous film specimens, it was concluded that the elastic moduli, tensile strengths, and elongation at break values for all copolyesters were similar as well, irrespective of the furan:bifuran molar ratio. Tensile moduli of approximately 2 GPa and tensile strengths up to 66 MPa were observed for amorphous film specimens prepared from the copolyesters. However, copolymerizing bifuran units into PBF allowed the glass transition temperature to be increased by increasing the amount of bifuran units. Besides enhancing the glass transition temperatures, the bifuran units also conferred the copolyesters with significant UV absorbance. This combined with the highly amorphous nature of the copolyesters allowed them to be melt-pressed into highly transparent films with very low ultraviolet light transmission. It was also found that furan–bifuran copolyesters could be as effective, or better, oxygen barrier materials as neat PBF or PBBf, which themselves were found superior to common barrier polyesters such as PET.

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The functionalization of inexpensive potato protein concentrate (PPC) is presented as a simple and easily scalable method to produce bio-based superabsorbent powders. Five nontoxic acylating agents were evaluated at different reaction temperatures for solvent-free acylation of the protein. The best results were obtained for succinic anhydride (SA) and a reaction temperature of 140 °C. These conditions resulted in efficient functionalization that provided formation of a useful network, which allowed high uptake of fluids and little material disintegration during the uptake, that is, due to protein hydrolysis during the functionalization. The SA-acylated PPC showed increased water and saline swelling capacities of 600 and 60%, respectively, as compared to untreated PPC. The acylated potato protein also showed a saline liquid holding capacity of approximately 50% after centrifugation at 1230 rpm for 3 min, as well as a significant blood swelling capacity of 530%. This blood swelling represents more than 50% of that of a commercial fossil-based superabsorbent (SAP) used for blood absorption in sanitary health products. The swelling properties of these inexpensive protein-based acylated materials highlight their potential as sustainable SAP materials (from industrial side-streams) in applications such as daily care products that are currently dominated by fossil-based SAPs.

Virgin biopolymers are often brittle and therefore need the addition of plasticizers to obtain the required mechanical properties for practical applications, for example, in bags and disposable kitchen items. In this article, based on a combined experimental and modeling approach, it is shown that it is possible to rank molecules with respect to their plasticization efficiency (depression in glass transition temperature with PVT data and reduced stiffness and strength) by using molecular dynamics simulations. Starch was used as the polymeric matrix material due to its promising potential as a sustainable, eco-friendly, biobased replacement for fossil-based plastics. Three polyols (glycerol, sorbitol, and xylitol), two ethanolamines (tri-and diethanolamine), and glucose were investigated. The results indicate that molecular simulations can be used to find the optimal plasticizer among a set of candidates or to design/identify better plasticizers in a complex polymer system. Glycerol was the most efficient of the six plasticizers, explained by it forming the least amount of hydrogen bonds, having the shortest hydrogen bond lifetimes and low molecular rigidity. Hence, not only was it possible to rank plasticizers, the ranking results could also be explained by the simulations.

Phthalate derivative plasticizers used in poly(vinyl chloride) (PVC) processing have been a subject of concern because of their possible toxicity. Hence, there is a growing interest toward new, nontoxic, "green" plasticizers. In this work, the performances of biobased plasticizers including esters of succinic, levulinic, oleic, and adipic acids were compared in reference to the conventional plasticizer bis(2-ethylhexyl) phthalate (aka dioctyl phthalate or DOP). For this purpose, molecular dynamics (MD) simulations were used to determine polymer/plasticizer interactions and to predict thermomechanical properties of polymer mixtures. The variation of glass temperatures (T g ) of the systems was investigated, and the stabilities of the polymer/ plasticizer mixtures were compared through the Flory−Huggins solubility parameter. The mechanical properties were investigated through nonequilibrium MD simulations. Young's modulus and yield strength values were predicted through stress−strain curves. The results suggest that succinic acid derivatives have the potential to replace phthalate derivatives due to their good solubility in PVC and their effectiveness in reducing the T g .