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.

In this study, magnetic core-shell Fe₃O₄@ZIF-8 was synthesized via a hydrothermal method and applied to Polyethylene terephthalate(PET) degradation. The catalytic degradation of PET by Fe₃O₄@ZIF-8 was carried out under atmospheric pressure, yielding high-value bis(2-hydroxyethyl) terephthalate (BHET) monomers. The as-synthesized Fe₃O₄@ZIF-8 core-shell composites possess hierarchical porosity with tunable nanoscale cavities. SEM and TEM analyses confirmed the core-shell morphology, with nanoparticles having a size distribution of 180–280 nm. The degradation product was identified as a high-purity, colorless, and transparent monomeric BHET through ¹H NMR and LC analyses. Based on a series of onefactor experiments and a Box-Behnken experimental design, the optimal process conditions were determined to be an alcoholysis temperature of 200°C, a catalyst dosage of 0.5 wt% (relative to PET mass), a reaction time of 50 min, and an ethylene glycol-to-PET mass ratio of 4.5:1. Under these conditions, the actual BHET yield reached 81.12%, closely matching the predicted value.