In the current study, we present the synthesis of novel low cost bio‐polyurethane compositions with variable mechanical properties based on castor oil and glycerol for biomedical applications. A detailed investigation of the physicochemical properties of the polymer was carried out by using mechanical testing, ATR‐FTIR, and X‐ray photoelectron spectroscopy (XPS). Polymers were also tested in short term in‐vitro cell culture with human mesenchymal stem cells to evaluate their biocompatibility for potential applications as biomaterial. FTIR analysis confirmed the synthesis of castor oil and glycerol based PU polymers. FTIR also showed that the addition of glycerol as co‐polyol increases crosslinking within the polymer backbone hence enhancing the bulk mechanical properties of the polymer. XPS data showed that glycerol incorporation leads to an enrichment of oxidized organic species on the surface of the polymers. Preliminary investigation into in vitro biocompatibility showed that serum protein adsorption can be controlled by varying the glycerol content with polymer backbone. An alamar blue assay looking at the metabolic activity of the cells indicated that castor oil based PU and its variants containing glycerol are non‐toxic to the cells. This study opens an avenue for using low cost bio‐polyurethane based on castor oil and glycerol for biomedical applications.

Methyl formate (MF) is a valuable platform molecule, the industrial production of which is far from being green. In this contribution, TiO2‐supported Pd(z)Pt(1−z) catalysts were found to be effective in the green synthesis of methyl formate (MF)—at T=323 K and ambient pressure—through methanol (MeOH) oxidation. Two series of catalysts with similar bulk Pd/(Pd+Pt) molar ratios, z, were prepared; one by a water‐in‐oil microemulsion (MicE) method and the other by an incipient wetness impregnation (IWI). The MicE method led to more efficient catalysts owing to a weak influence of z on particle size distributions and nanoparticles composition. Pd(z)Pt(1−z)‐MicE catalysts exhibited strong synergistic effects for MF production but weak synergistic effects for MeOH conversion. The catalytic performance of Pd(z)Pt(1−z)‐MicE was superior to that of Pd(z)Pt(1−z)‐IWI catalysts despite the latter displaying synergetic effects during the reaction. The catalytic behavior of TiO2‐supported Pd(z)Pt(1−z) catalysts was explained from correlations between XRD, TEM, and X‐ray photoelectron spectroscopy characterizations.

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