Thermo-responsive copolymers based on oligo(ethylene glycol) methacrylate (OEGMA, M_n = 300 g/mol) and pentafluorostyrene (PFS), coded PFG, were synthesized by RAFT polymerization, using a trithiocarbonate (CTTPC) as controlling agent. Different molar masses were targeted and dispersities lower than 1.51 were obtained. The thermally triggered self-assembly of the resulting PFG copolymers in water was investigated by dynamic light scattering (DLS). The lower critical solution temperature (LCST) slightly increased with the molecular weight in the 26–30 °C temperature range, whereas the sizes of the intermicellar aggregates formed upon self-assembly tended to decrease with increasing molecular weights (ranging from 1415 to 572 nm). The resulting thermally-induced polymer aggregates were then used to encapsulate and remove organic contaminants from water. Nile Red (NR) and Thiazole yellow G (TYG) were employed as hydrophobic and hydrophilic model contaminants, respectively. Experimental results evidenced that higher molecular weight copolymers removed up to 90% of NR from aqueous solution, corresponding to about 10 mg of dye per g of copolymer, regardless of NR concentration. The removal of TYG was lower with respect to NR, decreasing from about 40% to around 20% with TYG concentration. Finally, the copolymers were shown to be potentially recycled and reused in the treatment of contaminated water.

Transforming agri-food wastes into valuable products is crucial due to their significant environmental impact, when discarded, including energy consumption, water use, and carbon emissions. This review aims to explore the current research on the recovery of bioactive molecules with antimicrobial properties from agri-food waste and by-products, and discusses future opportunities for promoting a circular economy in its production and processing. Mainly, antibacterial molecules extracted from agri-food wastes are phenolic compounds, essential oils, and saponins. Their extraction and antimicrobial activity against a wide spectrum of bacteria is analyzed in depth. Also, their possible mechanisms of activity are described and classified based on their effect on bacteria, such as the (i) alteration of the cell membrane, (ii) inhibition of energy metabolism and DNA synthesis, and iii) disruption of quorum sensing and biofilm formation. These bioactive molecules have a wide range of possible applications ranging from cosmetics to food packaging. However, despite their potential, the amount of wastes transformed into valuable compounds is very low, due to the high costs relating to their extraction, technical challenges in managing supply chain complexity, limited infrastructure, policy and regulatory barriers, and public perception. For these reasons, further research is needed to develop cost-effective, scalable technologies for biomass valorization.

For the first time, ultrafiltration (UF) green membranes were prepared through a sustainable route by using PLA as a biopolymer and dihydrolevoclucosenone, whose trade name is Cyrene™ (Cyr), dimethyl isosorbide (DMI), and ethyl lactate (EL) as biobased solvents. The influence of physical-chemical properties of the solvent on the final membrane morphology and performance was evaluated. The variation of polymer concentration in the casting solution, as well as the presence of Pluronic^® (Plu) as a pore former agent, were assessed as well. The obtained results highlighted that the final morphology of a membrane was strictly connected with the interplaying of thermodynamic factors as well as kinetic ones, primarily dope solution viscosity. The pore size of the resulting PLA membranes ranged from 0.02 to 0.09 μm. Membrane thickness and porosity varied in the range of 0.090–0.133 mm of 75–87%, respectively, and DMI led to the most porous membranes. The addition of Plu to the casting solution showed a beneficial effect on the membrane contact angle, allowing the formation of hydrophilic membranes (contact angle < 90°), and promoted the increase of pore size as well as the reduction of membrane crystallinity. PLA membranes were tested for pure water permeability (10–390 L/m² h bar).

In this study, 3D printing technology is used to develop nanocomposite scaffolds based on polylactic acid (PLA) and hydroxyapatite (HA). PLA was functionalized with itaconic anhydride (PLA_f) via radical grafting to improve affinity with the inorganic nanofiller and accelerate hydrolytic degradation. Fourier‐transform infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopies confirmed the occurrence of chemical functionalization. Preliminary characterization of films of PLA, PLA_f and relative nanocomposites through water contact angle measurements highlighted an increase of wettability for PLA_f, due to the hydrophilic groups grafted onto polymer chain. Thermal analysis showed an increase of glass transition temperature (T_g) in PLA_f nanocomposites, likely due to enhanced matrix‐nanoparticle interactions. Scanning electron microscopy (SEM) analysis revealed more defined and homogeneous fibers for PLA_f‐HA5 and PLA_f‐HA10, meanwhile results from compression tests indicated improved processability and enhanced mechanical properties of nanocomposite PLA_f‐based scaffolds, as evidenced by increased values of Young modulus. Hydrolytic degradation studies in Phosphate Buffered Saline (PBS) solution showed greater weight loss and molecular weight decrease for PLA_f, PLA_f‐HA5, and PLA_f‐HA10, suggesting faster degradation due to increased hydrophilicity. Biological tests with human Mesenchymal Stem Cells (hMSCs) demonstrated that all scaffolds promoted cell proliferation, with PLA_f‐HA formulations showing higher effect on cellular behavior in terms of cell growth and alkaline phosphatase (ALP) levels, indicating that chemical functionalization improves cell attachment, proliferation and early osteogenic differentiation.Highlights: Functionalization of PLA enhances hydrophilicity and HA affinity. Nanocomposite scaffolds based on PLA_f are successfully developed by 3D printing. PLA functionalization enhances ink printability, making more uniform structures. PLA_f‐based scaffolds exhibit an accelerated hydrolytic degradation PLA_f‐HA scaffolds support cell adhesion and early osteogenic differentiation.