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In recent years, there has been a growing attempt to manipulate various properties of biodegradable materials to use them as alternatives to their synthetic plastic counterparts. Alginate is a polysaccharide extracted from seaweed or soil bacteria that is considered one of the most promising materials for numerous applications. However, alginate potential for various applications is relatively limited due to brittleness, poor mechanical properties, scaling-up difficulties, and high water vapor permeability (WVP). Choosing an appropriate plasticizer can alleviate the situation by providing higher flexibility, workability, processability, and in some cases, higher hydrophobicity. This review paper discusses the main results and developments regarding the effects of various plasticizers on the properties of alginate-based films during the last decades. The plasticizers used for plasticizing alginate were classified into different categories, and their behavior under different concentrations and conditions was studied. Moreover, the drawback effects of plasticizers on the mechanical properties and WVP of the films are discussed. Finally, the role of plasticizers in the improved processing of alginate and the lack of knowledge on some aspects of plasticized alginate films is clarified, and accordingly, some recommendations for more classical studies of the plasticized alginate films in the future are offered.

Phanerochaete chrysosporium is considered the model fungus for white rot fungi. It is the first basidiomycete whose genome has been completely sequenced. Its importance lies in the fact that its enzymatic system comprises the major enzymes involved in lignin degradation. Lignin is a complex and highly recalcitrant compound that very few living organisms are capable of degrading naturally. On the other hand, the enzymes produced by P. chrysosporium are also powerful agents for the mineralization into CO 2 and H 2 O of a wide range of aromatic compounds. However, these aromatic compounds are largely xenobiotic compounds with documented toxic effects on the environment and health. While the economic and environmental benefits of biodegradation with P. chrysosporium are well established, a thorough understanding of P. chrysosporium and its biodegradation processes is essential for successful biodegradation. Our aim of this critical literature review is to provide a concise and comprehensive insight of biodecomposition of organic substrate by P. chrysosporium .

The main drawbacks of flax fibers have been attributed to poor compatibility with polymer matrices as well as relatively high water absorption. The aforementioned properties are mainly due to the presence of hydrophilic hydroxyl functional groups on the backbone of the flax fibers. This study aims to convert primary alcoholic (OH) groups on the surface of flax fiber to carboxyl groups by using TEMPO oxidation in order to facilitate the silane treatment process. Subsequently, carboxyl groups can more easily interact with silane coupling agents. The surface functionality of as-received and treated fibers was characterized using Fourier transform infrared and X-ray photoelectron spectroscopy. Dynamic contact angle tensiometer was used to compare wettability of the oxidized and non-oxidized fibers after the silane treatment. The interaction between flax fiber and polymer was characterized using scanning electron microscopy (SEM). The results indicated that the TEMPO oxidation significantly improved the bonding efficiency of the silane coupling agents on the fiber surface. Thus, the compatibility between the flax fibers and the epoxy resin was improved. In addition, the water absorption of the modified fibers was remarkably reduced, while the contact angle of the flax fibers was increased.

This study investigates the impact of graphite (GR) concentration and particle size on the performance of conductive polymer composites (CPCs) using polyvinylidene fluoride (PVDF), polypropylene (PP), and polyethylene terephthalate (PET) as matrix materials. Composites were prepared with GR concentrations ranging from 20 to 60 wt. % and particle sizes categorized as G1 (5.9 µm), G2 (17.8 µm), and G3 (561 µm), and evaluated for their electrical, thermal, and mechanical properties. The investigation of the effect of graphite particle size on composite properties represents the main originality of this work. Among all composites, PVDF containing 60 wt. % of medium-sized G2 particles exhibited the lowest electrical resistivity (0.77 ohm·cm through-plane and 0.69 ohm·cm in-plane), along with the highest residual ash content (72%). In PP and PET matrices, incorporating 60 wt. % G2 particles resulted in through-plane resistivities of 11.3 ohm·cm and 1.6 ohm·cm, and in-plane resistivities of 5 ohm·cm and 1.2 ohm·cm, respectively, with thermal decomposition temperatures of 374 °C and 401 °C. Regarding mechanical performance and thermal stability, composites with small-sized G1 particles demonstrated superior performance due to their larger surface area and stronger matrix interactions. The PVDF/G1 (40/60 wt. %) composite achieved the highest flexural modulus (6.8 GPa), flexural strength (38.6 MPa), compressive modulus (0.28 GPa), and decomposition temperature (445 °C), highlighting its exceptional properties. These CPCs show significant promise for energy and electronic applications, particularly in the fabrication of bipolar plates for proton exchange membrane fuel cells, as well as in shielding materials and thermoelectric devices.

This study aims at measuring the interfacial properties of natural fibers in polypropylene composites by the mean of direct methods of characterization. Bamboo lamellae (BL) and polypropylene (PP) were used to produce laminated composites with continuous and homogenous interfaces. This research also focuses on the effect of maleic anhydride-grafted PP (MAPP) on the improvement of the PP/BL composites interfacial properties, which were measured by the means of the double cantilever beam (DCB), end-notched flexure (ENF) and short beam shear (SBS) methods. Flexural properties of the different composites were also determined using the three-point bending and single cantilever modes by dynamic mechanical analysis (DMA). The retention rates (Rr) of mechanical and interfacial properties were calculated on samples aged in hot water. Results reveal that MAPP induced a significant increase in flexural properties. This is undeniably related to an enhancement of affinity between PP and BL that was confirmed by DCB, ENF and SBS tests results. It was also highlighted that MAPP tends to limit degradation of the composite interfacial properties with,for instance, a critical fracture toughness (mode I) Rr of 97 % for MAPP coated composites against 56 % for the untreated composites.

Mycelium-based composites are self-grown biodegradable materials, made using agricultural residue fibers that are inoculated with fungi mycelium. The mycelium forms an interwoven three-dimensional filamentous network, binding every fiber particle together to create a rigid, lightweight composite material. Although having potential in packaging and in the construction industry, mycelium composites encounter molding limitations due to fiber size and oxygen access which hinder design capabilities and market engagement. To cope with these limitations, this study reports an alternative way to form mycelium composite using cut precultivated mycelium composite panels, laminated to biologically fuse into a unique assembly. By controlling the growth conditions of the mycelium network, it is possible to adjust physical properties such as flexural strength and strain energy density. These mycelium composite panels were fabricated from hemp fibers and Ganoderma lucidum mushroom. Seven different growth conditions were tested to increase layer adhesion and create the strongest assembly. Three-point flexural tests were conducted on ten samples extracted from each assembled panel triplicate set. The data collected in this study suggested that cultivating an opaque layer of mycelium on the surface of the panel before stacking can enhance total strain energy density by approximately 60%, compared to a single-layer mycelium composite of identical size. In addition, this eliminates abrupt material failure by dividing failure behavior into multiple distinct stages. Finally, by layering multiple thinner layers, the resulting mycelium composite could contain even higher mycelium proportions exhibiting augmented mechanical properties and higher design precisions opening market possibilities.

In this paper, a successive heating and cooling protocol was designed to investigate the self-nucleation behavior of poly(lactic acid), PLA. The main objective of this investigation was to study the efficiency of the α and α′ crystalline modifications of PLA. This was carried out by comparing crystallization temperatures upon cooling after self-nucleation of samples previously crystallized at various isothermal temperatures ranging from 80 to 130 °C. During heating to the partial melting range, three different mechanisms were observed for crystallized samples. For samples crystallized below 100 °C, an exothermic peak was detected prior the main melting peak which is ascribed to the α′–α solid-state transition. For samples crystallized between 100 and 120 °C, a melt recrystallization mechanism was observed. Finally, for samples crystallized above 120 °C, only melting of the α phase was detected. Upon cooling after partial melting, it was found that samples comprising a mixture of α and α′ exhibited the highest crystallization temperature, the highest nuclei density, and the smallest spherulite size. Moreover, it was observed that samples that were isothermally crystallized between 100 and 120 °C, heated up to partial melting, and then cooled back to room temperature exhibited two peculiar crystallization peaks at 100 and 120° C. This phenomenon was ascribed to the formation of α and α′ crystalline phases as revealed by X-ray diffraction. In addition, by slightly changing the temperature within the self-nucleation temperature range, a change of the proportion of each peak was observed.

This study presents a novel method for producing extrudable alginate-based films using continuous thermo-mechanical mixing, providing a scalable alternative to conventional solvent-casting techniques. The effects of glycerol concentration (30–50 wt%) and processing temperature (110–120 °C) on the films’ thermal, mechanical, and structural properties were systematically investigated. Structural characterization was performed using 1H NMR and FT-IR, and thermal transitions were analyzed via DSC (Differential Scanning Calorimetry) and DMA (Dynamic Mechanical Analysis). The glass transition temperature (Tg) of the alginate/glycerol/water system was modeled using the Gordon–Taylor equation. Glycerol incorporation significantly reduced Tg—by up to 76 °C with 40 wt% glycerol—and enhanced ductility and toughness, reaching 3.26 MJ/m3 at the optimal level. The influence of processing temperature was found to depend on plasticizer content: at lower glycerol levels, elevated temperatures decreased Tg and elongation at break, likely due to thermal degradation. However, films with higher glycerol content retained stable mechanical and thermal behavior across both temperature profiles. This work is among the first to explore how processing temperature affects extruded, plasticized pure alginate films. The findings provide key insights into the formulation and scalable production of bio-based packaging materials, highlighting the importance of optimizing both plasticizer concentration and processing parameters.

In this study, flax fibers were oxidized in order to improve the interfacial adhesion of cellulosic fibrils to a TiO 2 coating. The TiO 2 coating was created on the flax fiber by a Sol–Gel dip-coating technique. The effect of cellulose oxidation and the consequent TiO 2 grafting was studied on cellulose crystalline structures using X-ray diffraction. X-ray photoelectron spectroscopy was used to compare the reactivity of TiO 2 Sol with oxidized and non-oxidized cellulosic fibers. In addition, transmission electron microscopy and atomic force microscopy were applied to characterize the quality of the interface between the fibers and TiO 2 coating. Finally, the effect of cellulose oxidation on the mechanical properties of TiO 2 -grafted flax strands was investigated by tensile tests. The results showed that the oxidation increased significantly the reactivity of the cellulosic surfaces with TiO 2 Sol. This method was able to increase the quality of the interface between flax fiber and TiO 2 coating, which improved the thermal resistance of the fibers. Eventually, the oxidation of the fiber together with the TiO 2 grafting increased significantly both ductility and maximum tensile strength of the flax strands.

The increasing demand for sustainable materials in automotive applications, coupled with the critical need to address marine plastic pollution, presents an opportunity for innovative material development. This study explores composites made from recycled polyamide 6 (PA6) fishing nets reinforced with switchgrass fibers (0–30 wt%). The composite with 30 wt% switchgrass fibers increased tensile strength by 23% and Young’s modulus by 126% compared to unreinforced recycled PA6, achieving 93% of the tensile strength of commercial automotive-grade neat PA6 and surpassing another grade by 22%. However, higher fiber loading hindered processability, as evidenced by incomplete mold filling and reflected by a decrease in melt flow rate from 19.35 to 8.63 g/10 min. Thermal analysis revealed reduced crystallinity and crystallization temperatures with fiber addition, attributed to restricted polymer chain mobility. While dynamic mechanical analysis demonstrated improved stiffness below the glass transition temperature, scanning electron microscopy indicated optimal fiber-matrix adhesion at up to 20 wt% fiber loading, with aggregation at higher concentrations. These findings establish recycled fishing net-derived PA6/switchgrass fiber composites as a viable alternative to virgin materials in automotive applications, with mechanical properties comparable to commercial grades. Although the composites demonstrate enhanced mechanical strength and modulus, the significant reduction in ductility restricts their use to rigid, semi-structural components where flexibility is not critical. Future research should address processing challenges to enhance fiber dispersion and interfacial adhesion at higher loadings.