We have discovered that water-insoluble proteins (IM) isolated from whole soy meal (WM) have the capacity to improve the thermal stability of polypropylene (PP) wood composites without negatively impacting mechanical properties. We compared an undiluted composite to composites diluted with 5% by weight of a 3/1 w/w mixture of stearic acid and paraffin wax (SA/wax), 5% by weight IM, 5% by weight WM, 5% by weight of a 50/50 w/w mixture of IM in combination with SA/wax, and 5% by weight WM in combination with SA/wax. Water contact angle (CA) measurements and Fourier transform infrared spectroscopy (FTIR) revealed a synergy between IM and SA/wax, resulting in enhanced surface hydro - phobicity. Thermogravimetric analysis (TGA) showed lower weight loss in composites made with IM up to the onset of the degradation of PP, and reduced rates of lignin degradation, independently of the presence of SA/wax. Dynamic mechanical analysis (DMA) revealed higher modulus and lower viscoelastic loss resulting from the removal of water-soluble soy components from WM. Total reflectance ultraviolet spectroscopy (UV) showed that IM absorbs UV radiation strongly in the UV-B and UV-C regions. Collectively, these findings suggest that IM has the potential to become a multi-purpose additive for use in PP wood composites.

This study reports the fabrication and evaluation of layered scaffolds based on polylactide/polycaprolactone (PLPC) matrices for osteochondral-inspired designs. Bilayer architectures comprised a bone-facing layer with mineral phase (PLPC containing hydroxyapatite, HAP) and a cartilage-facing layer (PLPC containing only glucosamine sulfate (GS) or with simultaneous use of GS and an integrated electrospun gelatin/chondroitin sulfate (GEL/CS) fabric). The scaffolds exhibited interconnected porosity (55–60%) with a pore-size gradient (5–250 μm). Mechanical testing showed compressive strength up to 1 MPa and a layer-dependent compressive modulus, remaining within ranges reported for osteochondral tissues after six weeks of incubation. The layered configuration provided controlled GS release and reduced incubation-induced acidification; FTIR/XRD confirmed apatite precipitation in phosphate-buffered saline (PBS), enhanced when the GEL/CS fabric was present. After incubation, surface wettability shifted toward increased hydrophilicity, and permeability was modulated by scaffold composition, indicating tunable fluid-transport behavior. Overall, spatial separation of additives combined with a fibrous GEL/CS modifier enables control over mechanical response, release/medium evolution during incubation, and in vitro apatite-forming ability in PBS in a bilayer PLPC scaffold system.

Poly(lactic acid) (PLA) has attracted much attention and shows promising applications in numerous fields. In this study, PLA was plasticized using bio-based castor oil derivatives - hydrogenated castor oil (HCO) and castor oil glycidyl ether (COGE). These eco-blends were measured using a Fourier transform infrared spectrometer, a scanning electron microscope, a contact angle test, rheology, a differential scanning calorimeter, thermogravimetry, polarized optical microscopy, and a tensile test, respectively. The findings show that a core-shell morphology of COGE-HCO encapsulation is formed in PLA matrix, and the hydrogen bonding interaction and ring-opening chemical reaction among functional groups of the components greatly improve the compatibility, ductility, cold crystallization ability, and thermostability of the eco-blends, but the melt crystallization ability is hindered. The incorporation of HCO improves the hydrophobicity and oleophobicity of the eco-blends. Due to the combined effect of HCO and COGE, the melt viscosity reduces, and the Newtonian behavior enhances; the nucleation density and spherulitic growth of PLA increase. The strain at break of the PLA/HCO/COGE (90/7.5/2.5) blend reached 221%, which is 22.6 times higher than that of the neat PLA. These eco-blends present appropriate rheological, thermal, and mechanical properties, showing application scenarios in biodegradable packaging and disposable appliances.

In recent decades, numerous efforts have been dedicated to the investigation of eco-friendly non-isocyanate polyurethanes (NIPUs) as alternatives to conventional polyurethanes (PUs). Since isocyanates are classified by the EU as hazardous and toxic compounds, NIPUs offer a promising route to mitigate isocyanate-related health risks as well as other environmental concerns associated with traditional PU synthesis. In the present study, we report the synthesis as well as the detailed structural and thermal characterization of a new series of fully biobased non-isocyanate polyurethanes (NIPUs) based on aliphatic dicarboxylic acids of different chain lengths. The NIPUs were prepared via a two-step polyaddition reaction involving glycerol carbonate and diamine. Their synthesis enables a sustainable pathway to tailor NIPUs’ physicochemical properties via diacid structure control. Studies of their structure, thermal behavior and trends, morphological, and hydrolytic findings confirmed strong diacid chain length dependence on glass transition temperature (T_g ~13, 0, ‒5 and –23 °C), molecular weight, surface wettability, and enzymatic degradability. Short-chain diacids yielded NIPUs with rapid hydrolytic degradation, while their longer-chain analogs were hydrophobic and thermally stable. Contact angle measurements (~75–85°) also confirm these trends. The tunable properties position these materials among strong candidates for biomedical applications.

Bacterial cellulose (BC) is an eco-friendly biopolymer with outstanding structural and functional properties, offering promising applications in sustainable packaging and bio-based materials. In this study, we demonstrate the feasibility of producing BC via spontaneous fermentation, using grape pomace supplemented with sucrose as the sole carbon source, nutrient substrate, and microbial inoculum, without the addition of commercial strains or nitrogen supplements. Fermentation was conducted under static conditions, yielding biofilms with stable structural characteristics and BC production of up to 14.1 g/L, thereby confirming the efficiency of this low-cost, residue-based process. The films obtained exhibited well-organized polymeric networks, with thermal stability in the range of T_g ≈ 159–266 °C and mechanical resistance comparable to or higher than conventional biopolymers. Characterization confirmed reproducible chemical profiles, thermal stability, and measurable variation in mechanical performance, with a tensile strength ranging from 0.0001 to 105 MPa and an elongation at break of 15±5%. The process highlights a resource-efficient and sustainable pathway, adaptable to rural contexts and aligned with circular economic principles. While minor variations among replicates reflected the intrinsic variability of biological systems, mean values and standard deviations demonstrated reproducible physicochemical and mechanical properties. These findings demonstrate that BC derived from agro-industrial residues can be produced under simple, low-input conditions, opening opportunities for scalable valorization in functional and sustainable materials.