Bio-polyols from epoxidized soybean and linseed oils and caprylic acid or 3-phenyl butyric acid were prepared using an environmentally friendly, solvent-free method evaluating the presence of triethylamine as catalyst. Side reactions, leading to a cross-linking structure with high density, were reduced, introducing the catalyst and properly tuning the reaction conditions. A medium functionality value of around 3 along with a hydroxyl number up to around 90 mg KOH/g, narrow polydispersity index, and relatively low molecular mass up to 2400 g/mol were the experimental targets. From selected bio-polyols and an aliphatic partially bio-based isocyanate, a series of water blown polyurethane (PU) foams was produced, estimating the effect of the chemical nature of substituents in the polyol backbone on the PU properties. The apparent density of the foams was in the range of 79–113 kg/m³, with higher values for foams from the aromatic acid. Flexible polyurethane foams with open cell structure from bio-based polyols were obtained, with higher cavity size and lower pore sizes for foams from caprylic acid. The bio-based flexible PU foams showed comparable Young’s moduli (14–18 kPa) and compression deflection values (4.6–5.5 kPa) and exhibited an almost complete recovery of their initial size.

In this work, novel composites based on poly(ε-caprolactone) (PCL) were prepared and characterized in terms of morphological, thermal, rheological and mechanical properties. Hollow glass microspheres (HGM), alone or surface modified by treatment with (3-aminopropyl)triethoxysilane (APTES) in order to enhance the compatibility between the inorganic particles and the polymer matrix, were used to obtain lightweight composites with improved properties. The silanization treatment implies a good dispersion of filler particles in the matrix and an enhanced filler–polymer adhesion. The addition of HGM to PCL has relevant implications on the rheological and mechanical properties enhancing the stiffness of the material. Furthermore, the presence of HGM strongly interferes with the crystallization behavior and thermo-oxidative degradation of PCL. The increase of PCL crystallization rate was observed as a function of the HGM amount in the composites. Finally, rotational molding tests demonstrated the possibility of successfully producing manufactured goods in PCL and PCL-based composites on both a laboratory and industrial scale.

Water-blown polyurethane (PU) foams were prepared by bio-polyols from epoxidized linseed oils and caprylic acid in combination with toluene diisocianate (TDI). A series of terpenes (menthol, geraniol, terpineol, and borneol), natural compounds with recognized antibacterial properties, were included in the starting formulations to confer bactericidal properties to the final material. Foams additivated with Irgasan^®, a broad-spectrum antimicrobial molecule, were prepared as reference. The bactericidal activity of foams against planktonic and sessile E. coli (ATCC 11229) and S. aureus (ATCC 6538) was evaluated following a modified AATCC 100-2012 static method. Menthol-additivated foams showed broad-spectrum antibacterial activity, reducing Gram+ and Gram− viability by more than 60%. Foams prepared with borneol and terpineol showed selective antibacterial activity against E. coli and S. aureus, respectively. NMR analysis of foams leaking in water supported a bactericidal mechanism mediated by contact killing rather than molecule release. The results represent the proof of concept of the possibility to develop bio-based PU foams with intrinsic bactericidal properties through a simple and innovative synthetic approach.

Bio-polyols (BPOs), characterized by a hydroxyl number up to around 90 mg KOH/g, narrow polydispersity index and relatively low molecular mass up to 2000 g/mol, were synthetized from partially and completely epoxidized soybean and linseed oils and caprylic acid or 3-phenyl butyric acid. These BPOs were used in the presence of toluene diisocyanate to produce polyurethane (PU) foams by using a quasi-prepolymer method involving a two-step reaction. A detailed structural investigation of the prepolymers from toluene diisocyanate and both BPOs and polypropylene glycol was conducted by SEC and solution NMR. The apparent density of the foams was in the range of 40–90 kg/m³, with higher values for foams from the aromatic acid. All the foams showed an open-cell structure with uniform and regular shape and uniform size. The specific Young’s moduli and compression deflection values suggest superior mechanical properties than the reference foams. The novel synthesized polyurethanes are excellent candidates to partially replace petroleum-based materials.