Monodisperse superparamagnetic Fe3O4 nanoparticles coated with oleic acid were prepared by thermal decomposition of Fe(III) glucuronate. The shape, size, and particle size distribution were controlled by varying the reaction parameters, such as the reaction temperature, concentration of the stabilizer, and type of high-boiling-point solvents. Magnetite particles were characterized by transmission electron microscopy (TEM), as well as electron diffraction (SAED), X-ray diffraction (XRD), dynamic light scattering (DLS), and magnetometer measurements. The particle coating was analyzed by atomic absorption spectroscopy (AAS) and attenuated total reflection (ATR) Fourier transform infrared spectroscopy (FTIR) spectroscopy. To make the Fe3O4 nanoparticles dispersible in water, the particle surface was modified with α-carboxyl-ω-bis(ethane-2,1-diyl)phosphonic acid-terminated poly(3-O-methacryloyl-α-D-glucopyranose) (PMG-P). For future practical biomedical applications, nontoxicity plays a key role, and the PMG-P&Fe3O4 nanoparticles were tested on rat mesenchymal stem cells to determine the particle toxicity and their ability to label the cells. MR relaxometry confirmed that the PMG-P&Fe3O4 nanoparticles had high relaxivity but rather low cellular uptake. Nevertheless, the labeled cells still provided visible contrast enhancement in the magnetic resonance image. In addition, the cell viability was not compromised by the nanoparticles. Therefore, the PMG-P&Fe3O4 nanoparticles have the potential to be used in biomedical applications, especially as contrast agents for magnetic resonance imaging.

Polycarbonate and polyurethane scraps from end-oflife vehicles were converted into liquid recycled polyols with hydroxyl number around 300 mgKOH•g −1 by using medium chain glycerides of coconut oil. The obtained polyols were used for preparation of low-density rigid polyurethane foams. It was found that up to 50 wt % of the virgin petrochemical polyol can be replaced by the recycled polyols without any negative effect on the foaming process. The obtained foams exhibited the apparent density of 40−44 kg•m −3 , the homogeneous cellular structure with a high content of closed cells (>91 vol %) and the beneficially low value of lambda coefficient (∼23 mW•m −1 •K −1 ). The exceptionally high compressive strength (>350 kPa in parallel to foam rise direction) of the rigid PUR foams with 50 wt % of recycled polyol derived from polycarbonate scrap resulted probably from the unique structure of recycled polyol combining rigid aromatic segments together with flexible coconut oil glyceride units. In conclusion, this approach utilizing the renewable coconut oil-derived reagent provides a sustainable recycling solution for two major plastics from automotive waste.

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