Synthesis and Assessment of Novel Sustainable Antioxidants with Different Polymer Systems.

Antioxidants are essential to the polymer industry. The addition of antioxidants delays oxidation and material degradation during their processing and usage. Sustainable phenolic acids such as 4-hydroxybenzoic acid or 3,4-dihydroxybenzoic acid were selected.

Study of the water sorption and barrier performances of potato starch nano-biocomposites based on halloysite nanotubes.

The barrier performances, in terms of water vapor sorption properties, gas and water barrier performances were analyzed on different starch-based nano-biocomposites. These multiphase systems were elaborated by melt blending starch and halloysite nanotubes at different contents with different plasticizers (glycerol, sorbitol and a mix of both polyols). The influence of the composition was investigated onto the structure, morphology, water sorption and barrier performances.

Ferulic Acid as Building Block for the Lipase-Catalyzed Synthesis of Biobased Aromatic Polyesters.

Enzymatic synthesis of aromatic biobased polyesters is a recent and rapidly expanding research field. However, the direct lipase-catalyzed synthesis of polyesters from ferulic acid has not yet been reported. In this work, various ferulic-based monomers were considered for their capability to undergo CALB-catalyzed polymerization.

MIXed plastics biodegradation and UPcycling using microbial communities: EU Horizon 2020 project MIX-UP started January 2020.

This article introduces the EU Horizon 2020 research project MIX-UP, "Mixed plastics biodegradation and upcycling using microbial communities". The project focuses on changing the traditional linear value chain of plastics to a sustainable, biodegradable based one. Plastic mixtures contain five of the top six fossil-based recalcitrant plastics [polyethylene (PE), polyurethane (PUR), polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS)], along with upcoming bioplastics polyhydroxyalkanoate (PHA) and polylactate (PLA) will be used as feedstock for microbial transformations.

Breakthrough in polyurethane bio-recycling: An efficient laccase-mediated system for the degradation of different types of polyurethanes.

Development of green, efficient and profitable recycling processes for plastic material will contribute to reduce the expanding plastic pollution and microplastics accumulation in the environment. Polyurethanes (PU) are versatile polymers with a large range of chemical compositions and structures. This variability increases the complexity of PU waste management.

Towards bio-upcycling of polyethylene terephthalate.

Over 359 million tons of plastics were produced worldwide in 2018, with significant growth expected in the near future, resulting in the global challenge of end-of-life management. The recent identification of enzymes that degrade plastics previously considered non-biodegradable opens up opportunities to steer the plastic recycling industry into the realm of biotechnology. Here, the sequential conversion of post-consumer polyethylene terephthalate (PET) into two types of bioplastics is presented: a medium chain-length polyhydroxyalkanoate (PHA) and a novel bio-based poly(amide urethane) (bio-PU).

Green Recycling Process for Polyurethane Foams by a Chem-Biotech Approach.

Polyurethanes (PUs) are highly resistant materials used for building insulation or automotive seats. The polyurethane end-of-life issue must be addressed by the development of efficient recycling techniques. Since conventional recycling processes are not suitable for thermosets, waste management of PU foam is particularly questioning.

Characterization of the enzymatic degradation of polyurethanes.

For decades, polyurethanes (PUR) have mainly been synthesized for long-term applications and are therefore highly persistent in the environment. Proper waste disposal approaches, including recycling techniques, must be developed to limit the accumulation of PUR in the environment. Evaluation of enzymatic polyurethane degradation is needed for the development of enzymatic recycling.

Isolation of Low Dispersity Fractions of Acetone Organosolv Lignins to Understand their Reactivity: Towards Aromatic Building Blocks for Polymers Synthesis.

Two organosolv lignins extracted during pilot runs of the Fabiola process were analyzed, fractionated and chemically modified with ethylene carbonate (EC) to produce building blocks suitable for polymer synthesis. Isolation of low dispersity fractions relied on the partial solubility of the lignins in organic solvents. Lignins solubility was first evaluated and analyzed with Hansen and Kamlet-Taft solubility parameters, showing a good correlation with the solvents dipolarity/polarizability parameter π*.

Morphology and properties of thermoplastic starch blended with biodegradable polyester and filled with halloysite nanoclay.

The incorporation of halloysite clay nanotubes (HNTs) into thermoplastic starch/poly(butylene adipate-co-terephthalate) (TPS/PBAT) blends has been investigated with the aim of improving the compatibility and properties of the matrix. TPS/PBAT/HNTs nano-biocomposites with different TPS/PBAT weight fractions and HNTs contents were elaborated using a melt blending process, and their morphology and properties were investigated. The TPS80/PBAT20 and TPS20/PBAT80 blends exhibited dispersed phases of small droplets of PBAT or TPS, respectively, whereas the TPS50/PBAT50 blend presented a more homogeneous structure.

Optimized Bioproduction of Itaconic and Fumaric Acids Based on Solid-State Fermentation of Lignocellulosic Biomass.

The bioproduction of high-value chemicals such as itaconic and fumaric acids (IA and FA, respectively) from renewable resources via solid-state fermentation (SSF) represents an alternative to the current bioprocesses of submerged fermentation using refined sugars. Both acids are excellent platform chemicals with a wide range of applications in different market, such as plastics, coating, or cosmetics. The use of lignocellulosic biomass instead of food resources (starch or grains) in the frame of a sustainable development for IA and FA bioproduction is of prime importance.

Evaluation of biological degradation of polyurethanes.

Polyurethanes (PU) are a family of versatile synthetic polymers intended for diverse applications. Biological degradation of PU is a blooming research domain as it contributes to the design of eco-friendly materials sensitive to biodegradation phenomena and the development of green recycling processes. In this field, an increasing number of studies deal with the discovery and characterization of enzymes and microorganisms able to degrade PU chains.

Preparation and Characterization of Thermoplastic Potato Starch/Halloysite Nano-Biocomposites: Effect of Plasticizer Nature and Nanoclay Content.

Nano-biocomposites based on halloysite nanoclay and potato starch were elaborated by melt blending with different polyol plasticizers such as glycerol, sorbitol or a mixture of both. The effects of the type of plasticizer and clay content on potato starch/halloysite nano-biocomposites were studied. SEM analyses combined with ATR-FTIR results showed that a high content of sorbitol had a negative effect on the dispersion of the halloysite nanoclay in the starchy matrix.

Enzymatic recycling of thermoplastic polyurethanes: Synergistic effect of an esterase and an amidase and recovery of building blocks.

Biological recycling of polyurethanes (PU) is a huge challenge to take up in order to reduce a large part of the environmental pollution from these materials. However, enzymatic depolymerization of PU still needs to be improved to propose valuable and green solutions. The present study aims to identify efficient PU degrading enzymes among a collection of 50 hydrolases.

Isolation and characterization of different promising fungi for biological waste management of polyurethanes.

As a highly resistant polymer family, polyurethanes (PU) are responsible for increasing environmental issues. Then, PU biodegradation is a challenging way to develop sustainable waste management processes based on biological recycling. Since the metabolic diversity of fungi is a major asset for polymer degradation, nearly thirty strains were isolated from sampling on six different PU wastes-containing environments.

Original Macromolecular Architectures Based on poly(ε-caprolactone) and poly(ε-thiocaprolactone) Grafted onto Chitosan Backbone.

Polyester and/or polythioester grafted chitosan copolymers were synthesized. For that, poly(ε-caprolactone) (PCL), poly(ε-thiocaprolactone) (PTCL), and their copolymers were first synthesized by ring opening polymerization. Copolymers with caprolactone:thiocaprolactone (CL:TCL) molar ratios of 2:1, 1:1, 1:2 were synthesized.

Biotic and Abiotic Synthesis of Renewable Aliphatic Polyesters from Short Building Blocks Obtained from Biotechnology.

Biobased polymers have seen their attractiveness increase in recent decades thanks to the significant development of biorefineries to allow access to a wide variety of biobased building blocks. Polyesters are one of the best examples of the development of biobased polymers because most of them now have their monomers produced from renewable resources and are biodegradable. Currently, these polyesters are mainly produced by using traditional chemical catalysts and harsh conditions, but recently greener pathways with nontoxic enzymes as biocatalysts and mild conditions have shown great potential.

Enzymatic Synthesis of Amino Acids Endcapped Polycaprolactone: A Green Route Towards Functional Polyesters.

ε-caprolactone (CL) has been enzymatically polymerized using α-amino acids based on sulfur (methionine and cysteine) as (co-)initiators and immobilized lipase B of (CALB) as biocatalyst. In-depth characterizations allowed determining the corresponding involved mechanisms and the polymers thermal properties. Two synthetic strategies were tested, a first one with direct polymerization of CL with the native amino acids and a second one involving the use of an amino acid with protected functional groups.

Innovative plasticized alginate obtained by thermo-mechanical mixing: Effect of different biobased polyols systems.

Plasticized alginate films with different biobased polyols (glycerol and sorbitol) and their mixtures were successfully prepared by thermo-mechanical mixing instead of the usual casting-evaporation procedure. The microstructure and properties of the different plasticized alginate formulations were investigated by SEM, FTIR, XRD, DMTA and uniaxial tensile tests. SEM and XRD results showed that native alginate particles were largely destructured with the plasticizers (polyols and water), under a thermo-mechanical input.

Original method for synthesis of chitosan-based antimicrobial agent by quaternary ammonium grafting.

Functionalized high molar mass chitosan derivatives with increased antibacterial properties were prepared by the reaction of chitosan with different quaternary ammonium salts. Benzalkonium bromide, pyridinium bromide and triethyl ammonium bromide were synthesized by a quaternization reaction between 1,4-dibromobutane and the respective tertiary amines (N, N-dimethylbenzylamine, triethylamine and pyridine) to obtain three ammonium salts with a bromide end-group capable of reacting with a functional group from the chitosan backbone. The ammonium salts were chemically grafted along the chitosan macromolecular chains.

Enzymatic Synthesis of a Bio-Based Copolyester from Poly(butylene succinate) and Poly((R)-3-hydroxybutyrate): Study of Reaction Parameters on the Transesterification Rate.

The enzyme-catalyzed synthesis of fully biobased poly(3-hydroxybutyrate-co-butylene succinate) (poly(HB-co-BS)) copolyesters is reported for the first time. Different Candida antarctica lipase B (CALB)-catalyzed copolyesters were produced in solution, via a one-step or a two-step process from 1,4-butanediol, diethyl succinate, and synthesized telechelic hydroxylated poly(3-hydroxybutyrate) oligomers (PHB-diol). The influence of the ester/hydroxyl functionality ratio, catalyst amount, PHB-diol oligomer chain length, hydroxybutyrate (HB) and butylene succinate (BS) contents, and the nature of the solvent were investigated.

Nanoclays for Lipase Immobilization: Biocatalyst Characterization and Activity in Polyester Synthesis.

The immobilization of lipase B (CALB) was performed by physical adsorption on both neat and organo-modified forms of sepiolite and montmorillonite. The influence of different parameters, e.g.

Itaconic and Fumaric Acid Production from Biomass Hydrolysates by Aspergillus Strains.

Itaconic acid (IA) is a dicarboxylic acid included in the US Department of Energy's (DOE) 2004 list of the most promising chemical platforms derived from sugars. IA is produced industrially using liquid-state fermentation (LSF) by Aspergillus terreus with glucose as the carbon source. To utilize IA production in renewable resource-based biorefinery, the present study investigated the use of lignocellulosic biomass as a carbon source for LSF.

Star-pseudopolyrotaxane organized in nanoplatelets for poly(ε-caprolactone)-based nanofibrous scaffolds with enhanced surface reactivity.

Herein, it is demonstrated that star pseudopolyrotaxanes (star-pPRs) obtained from the inclusion complexation of α-cyclodextrin (CD) and four-branched star poly(ε-caprolactone) (star-PCL) organize into nanoplatelets in dimethyl sulfoxide at 35 °C. This peculiar property, not observed for linear pseudopolyrotaxanes, allows the processing of star-pPRs while preserving their supramolecular assembly. Thus, original PCL:star-pPR core:shell nanofibers are elaborated by coaxial electrospinning.

Polyhydroxyalkanoates: waste glycerol upgrade into electrospun fibrous scaffolds for stem cells culture.

This integrated study shows that waste glycerol can be bio-valorized by the fabrication of electrospun scaffolds for stem cells. Human mesenchymal stem cells (hMSC) provide an interesting model of regenerating cells because of their ability to differentiate into osteo-, chrondro-, adipo- and myogenic lineages. Moreover, hMSC have modulatory properties with potential on treatment of immunologic diseases.