The potential of Adansonia digitata (baobab) pulp polysaccharides (BB), combined with whey protein (WP) and alginate (ALG), was evaluated as a novel pharmaceutical excipient to enhance the viscosity, swelling behavior, controlled release, and mucoadhesive properties of hydrogels prepared by the ionotropic gelation technique. Hydrogels based on BB, WP, and ALG, alone or in combinations (WP/BB, WP/ALG, ALG/BB, and WP/ALG/BB), were characterized by infrared spectroscopy and zeta potential measurements. Rheological, swelling, controlled release, and mucoadhesion studies were conducted to assess the functional contribution of BB and its synergistic effects with WP and ALG. All polymers exhibited viscoelastic solid behavior (G' > G″). For each polymer, with or without crosslinking, molecular interactions were observed, leading to variations in the Tan δ parameter. The crosslinked WP/ALG/BB hydrogel exhibited reduced polymer swelling and provided a more sustained release of the incorporated active substance. In vitro and ex vivo studies demonstrated strong interactions between the polymeric matrices and intestinal mucus, with the WP/ALG/BB system showing the highest mucoadhesion. Further in vivo investigations are needed to confirm the ability of BB to enhance the oral bioavailability of active substances. Overall, Adansonia digitata pulp polysaccharides, in combination with whey protein and alginate, represent a promising natural excipient for the development of bioadhesive hydrogels and cold-gelled delivery systems in pharmaceutical formulations.

The encapsulation of molecules with different physicochemical properties (theophylline, blue dextran, salicylic acid and insulin) in whey protein (WP) and alginate (ALG) microparticles (MP) for oral administration was studied. MP based on WP/ALG were prepared by a cold gelation technique and coated with WP solution after reticulation. Molecules influenced polymer solution viscosity and elasticity, resulting in differences regarding encapsulation efficiency (from 23 to 100%), MP structure and swelling (>10%) and in terms of pH tested. Molecule release was due to diffusion and/or erosion of MP and was very dependent on the substance encapsulated. All the loaded MP were successfully coated, but variation in coating thickness (from 68 to 146 µm) and function of the molecules encapsulated resulted in differences in molecule release (5 to 80% in 1 h). Gel rheology modification, due to interactions between WP, ALG, calcium and other substances, was responsible for the highlighted differences. Measuring rheologic parameters before extrusion and reticulation appeared to be one of the most important aspects to study in order to successfully develop a vector with optimal biopharmaceutical properties. Our vector seems to be more appropriate for anionic high-molecular-weight substances, leading to high viscosity and elasticity and to MP enabling gastroresistance and controlled release of molecules at intestinal pH.

As a new generation of green solvents, deep eutectic solvents (DESs) are considered a promising alternative to current harsh organic solvents and find application in many chemical processing methods such as extraction and synthesis. DESs, normally formed by two or more components via various hydrogen bond interactions, offer high potential as medium for biocatalysis reactions where they can improve efficiency by enhancing substrate solubility and the activity and stability of the enzymes. In the current study, the stabilization of Humicola insolens cutinase (HiC) in natural deep eutectic solvents (NADESs) was assessed. The best hydrogen bond donor among sorbitol, xylitol, erythritol, glycerol and ethylene glycol, and the best acceptor among betaine, choline chloride, choline acetate, choline dihydrogen citrate and tetramethylammonium chloride, were selected, evaluating binding energies and molecular orientations through molecular docking simulations, and finally used to prepare NADES aqueous solutions. The effects of component ratio and NADES concentration on HiC thermostability at 90 °C were also investigated. The choline dihydrogen citrate:xylitol, in a 1:1 ratio with a 20 wt% concentration, was selected as the best combination in stabilizing HiC, increasing its half-life three-fold.

Time–temperature superposition was used to process the values of unreacted isocyanate fractions from several temperatures. TTS method application might allow the prediction of kinetic trends without the need for a large volume of accurate data.

The strength of starch-based bioplastics is a challenge, we tried to overcome this limitation by using electromagnetic radiation in the visible range.Synthetically obtained retrograde bioplastics were subjected to radiation from an Edison-type incandescent lamp.A cross-linked network is obtained within the bioplastic matrix considerably attenuating the usual hygroscopicity of starch and increasing the ability to resist rupture.After this positive behavior, the bioplastics were colored in order to optimize the action of light radiation.The results show a stronger and more compact bioplastic.The green-colored bioplastics show the best performance in the optimization of the resistance.

The work carried out here opens another perspective in the valorization of sweet potatoes produced in Congo Brazzaville other than those proposed by BOULA and all. We have shown in this work that the hydrophilic property of starch which limits the production of starch-based bioplastics can be inhibited by using the effects of photonic incandescence. Indeed, light significantly impacts the bioplastic matrix causing a decrease of the sites likely to bind water molecules. However, it would be desirable to apply rheology for a better follow-up of this cross-linking phenomenon. The synthesized retrograde bioplastic having undergone a photonic stress shows better physical properties to be used as packaging and thus to answer the environmental protection.

Tire and Road Wear Particles (TRWP) are polymer-based microparticles emissions that are emitted in the environment during tire usage. Growing efforts are currently being made to quantify these emissions, characterize the leachates or assess their environmental impact. This study aimed at investigating the effect of aging on TRWP composition. Cryomilled tire tread particles (CMTTP) and TRWP were exposed for different durations to three aging conditions: accelerated thermal and photochemical aging, and natural outdoor aging. Particles were then extracted with cyclohexane/ethanol. Time-concentrations profiles of 23 additives and transformation products present in these extracts were determined by UHPLC-HRMS. Several chemicals, such as N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6-PPD) or 1,3-diphenylguanidine (DPG), decayed exponentially under all aging conditions, with half-lives of a few days of magnitude under artificial photo-aging against dozens of days under purely thermal aging at 60°C. Natural aging profiles lied between those 2 laboratory aging conditions. Other chemicals, such as 6PPD-quinone, presented bell-shaped concentration profiles within CMTTP when particles were exposed to UV-light. Starting from an initial load of ca. 1 µg/g, 6PPD-quinone reached a maximum of ca. 20 µg/g within a month under natural aging. For TRWP, the initial load of 6PPD-quinone was 23-30 µg/g and decreased exponentially under natural aging with a half-life below one month. Purely thermal aging induced a significantly slower decay of 6PPD-quinone within TRWP (half-life of half a year) emphasizing a greater stability and persistence in environment compartments without light. This study highlighted that the more readily accessible CMTTP could be considered as a reasonable proxy of TRWP to investigate the fate of chemicals within rubber particles, at least from a qualitative standpoint. Overall, the concentrations of 20 of the evaluated chemicals decreased by more than 50% within 50 days under natural aging.

Poly(butylene succinate-co-butylene adipate) (PBSA)-based materials are receiving growing attention in the packaging industry for their promising biodegradability. However, poor gas barrier properties and low durability of biodegradable polymers, such as PBSA, have limited their wide-spread use in food packaging applications. Here we report a scalable solution to improve gas barrier properties and stabilize PBSA against photo-aging, with minimal modifications to the biodegradable polymer backbone by using a commercially available and biocompatible layered double hydroxide (LDH) filler. We investigate and compare the mechanical, gas barrier, and photoaging properties of PBSA and PBSA-LDH nanocomposite films produced on a pilot scale. An increase in rigidity in the nanocomposite was observed upon addition of LDH fillers to neat PBSA, which direct the application of neat PBSA and PBSA-LDH nanocomposite to different food packaging applications. The addition of LDH fillers into neat PBSA improves the oxygen and water vapour barriers for the PBSA based nanocomposites, which increases the attractiveness of PBSA material in food packaging applications. Through changes in the viscoelastic behaviour, we observe an improved photo-durability of photoaged PBSA-LDH nanocomposites compared to neat PBSA. It is clear from our studies that the presence of LDH enhances the lifetime durability and modulates the photodegradation rate of the elaborated biocomposites.

There is a serious need to assess the evolution of transitions from a linear to a Circular Economy (CE) using tools, metrics, and measurement indicators that not only are able to take into account the circularity, but also the other sustainability performances of products. Currently, most measurement tools do not lead to valuable decisions, as they do not capture the performance of the CE in its entirety, resulting in poorer performance on certain aspects, such as the environment. In addition, the lack of industry-specific indicators may hinder the adaptation of CE due to the different structures and functions of products. Consequently, this paper proposes a circularity indicator adapted from the Material Circularity Indicator (MCI) for the plastic industry, specifically Multi-layer Plastic Packaging (MPP). The adapted indicator is expanded based on the quality of recycled polymers by defining a new utility factor (X) as the polymers' intensity of re-use. It also highlights that it is necessary to combine a circularity indicator with Life Cycle Assessment (LCA) for viable end-of-life (EOL) management. To illustrate the use of the proposed indicator and the trade-offs between circularity and environmental impacts, a case study on three-layer plastic packaging is applied to two end-of-life scenarios (Incineration, and closed-loop mechanical recycling). The results show that an increase in material circularity generally decreases the environmental impacts. However, recycling was found to have a higher impact than incineration on some impact categories such as land use and freshwater eutrophication.

Fused deposition modelling is a rapidly growing additive manufacturing technology due to its ability to build functional parts with complex geometries. The mechanical properties of a built part depend on several process parameters. The effect of wood content on the properties of 3D printed parts has been studied. Four types of filaments using poly(butylene succinate-co-adipate) (PBSA) with different reinforcement levels of Typha stem powder 0%, 5%, 10%, and 15% by weight were used for 3D printing. The density of the filaments and parts printed in this study increased with the Typha stem powder content. The thermal stability, mechanical performance, and viscoelastic properties of the different biocomposite filaments and 3D printed objects were analysed. The results show an increase in the crystallisation kinetics and a slight decrease in the thermal stability of the biomaterials. Compared to virgin PBSA FDM filaments, the PBSA biocomposite filament filled with Typha stem powder showed an increase in the tensile strength of the parts and specimens from 2.5 MPa to 8 MPa and in the modulus of elasticity from 160 MPa to 375 MPa, respectively, with additions of 5%, 10%, and 15% by mass. The addition of Typha stem fibres generated an increase in the elastic behaviour and relaxation time of the biomaterial structure, visualised by increases in the values of the viscosity components. The surface morphology reveals a decrease in the porosity of the printed samples.

Biocomposites based on polypropylene (PP) and typha fibre were prepared using a twin-screw extruder and different characterisation techniques, namely thermal, mechanical, rheological and morphological analysis, to evaluate the effects of typha stem powder on the final properties of the biomaterials.The rheological characterisation showed that the G' and G" values of pure PP and biocomposites increase with the rate of reinforcement and are related to agglomeration phenomena of Typha fibres which reduce the sliding or flow between them inside the biocomposite.The viscosity of the composites is strongly influenced by the shear rate.Shear thinning behaviour of the melt was observed.The results of the mechanical tests show an increase in tensile young's modulus up to 45% and an increase in tensile strength up to a critical value of 25% for typha stems, which can be attributed to the good interfacial adhesion between the matrix and the filler.Differential Scanning Calorimetry (DSC) measurements indicate the presence of crystalline phases and a slight difference of about 3°C between the melting temperatures.Typha acts as a nucleating agent.Micrographs show the diffuse aspect of the fibre distribution in the matrix.The good wettability of typha fibres by polypropylene contributes to the reduction of microcavities, which has a positive effect on the mechanical properties up to a certain level of reinforcement.Finally, the thermogravimetric analysis shows that typha fibre decreases the thermal stability of the biomaterials.

Objective: The objective of this work is to study the artificial ageing of semi-rigid and plasticized polyvinyl chloride (PVC) stabilized with epoxidized sunflower oil (ESO) as a biobased derivative in combination with zinc and calcium stearates. Methods: For comparison, a formulation of PVC plasticized and stabilized with epoxidized soya bean oil (ESBO) was considered. Artificial ageing was carried out during the 304 hours. Samples were taken off after: 48, 146, 234 and 304 hours and then characterized. The evolution of density, glass transition temperature and morphology, was followed as a function of the time. The structural modifications of polymer were analyzed by Fourier transform infrared spectroscopy in attenuated total reflectance and transmission modes. Results: The results showed a little decrease of density, a considerable increase of the glass transition temperatures values and a change of morphology. All changes in the properties of PVC relate to formation of new chemical structures. Conclusion: Globally, it was found that ESO exhibited similar performances to those of ESBO.

The study of the polymerization of a vegetable oil has a double interest; industrial but especially food. Industrial because polymers based on vegetable oil are in line with sustainable development; food because an oil which polymerizes easily is a danger for human consumption. Three situations of Cucurbita pepo oil polymerization are carried out in the course of time, the factor retained being temperature. A monitoring of the evolution of the enthalpy by temperature variation by the DSC method allows to report the polymerization of this oil. It happens that a polymerization is triggered in the oil matrix but it seems to fade very quickly, this behavior is general because after sweeping a temperature range of 80°C; 100°C and 150°C adding different amounts of Irgacure: the Cucurbita pepo oil resists polymerization through its antioxidant compounds. However, a photolysis of this oil carried out over 8 days shows that it effectively polymerizes after 144 hours, which proves the great capacity of antioxidant compounds to protect this oil. The analyses carried out at 25°C aim to simulate the behavior of the oil at room temperature. The results reveal good resistance to both thermochemical and photochemical polymerization, which opens up great prospects for its development in the food industry and in nutrition.

An eco-friendly solution to produce new material for the material extrusion process is to use quarry waste as filler for biopolymer composites. A quarry waste that is still studied little as a filler for polymer composites is pozzolan. In this study, the optimization of the formulations and processing parameters of composites produced with pozzolan and bio-based polyethylene for 3D printing technology was performed. Furthermore, a precision irrigation system in the form of a drip watering cup was designed, printed, and characterized. The results showed that the presence of the pozzolan acted as a reinforcement for the composite material and improved the cohesion between the layers of the 3D printed objects. Furthermore, the optimization of the process conditions made it possible to print pieces of complex geometry and permeable parts for the control of the water flow rates with an order of magnitude in the range from mL/h to mL/day.

Due to the demand from society for the consumption of ecological polymeric materials, one of the polymers that have satisfied this request is the poly (lactic acid) (PLA). This polymer is derived from renewable resources, it is recyclable and biodegradable. It presents a good understanding between the promising properties and the cost. However, a route to increase the mechanical properties and reduce the cost of PLA is the elaboration of PLA based biocomposites by using fillers from natural waste. In this work, The effect of Typha content on the morphological, rheological, thermal and mechanical properties of PLA matrix was studied. Four formulations were produced with different mass concentrations. The results showed an increase in the viscoelastic properties, as a function of the Typha stem powder concentration. The DSC analysis showed an increase in the crystallinity rate of the various composites confirming the nucleating effect provided by the filler. TGA analysis indicated a decrease in the decomposition temperature of the composites. Mechanical tensile tests have shown a significant improvement in the mechanical properties mainly for the samples containing 45% (w/w) of Typha powder.

A new eco-composite polymer for material extrusion fabrication based on fine fraction pozzolan waste was developed. In addition, the composite materials obtained were used to produce a self-watering pot with complex geometry and a permeable porous part to regulate the passage of water from the storage area to the roots of the plant. Moreover, the system was devised with a cover characterized by a UV-B barrier film. The results have shown the possibility of the 3D printing of complex geometric parts as microporous structures or thin films using a composite based on poly lactic acid (PLA) and pozzolan. The pozzolan has an effect of reinforcement for the composite and at the same time improves the cohesion between the layers of the part during printing.