Metathesis Copolymerization of Cyclooctene with Epoxycyclooctene Followed by One-Pot Hydrogenation of Reaction Products

A synthetic route to metathesis and hydrogenated copolymers of cyclooctene (COE) with epoxycyclooctene (ECOE) via tandem metathesis copolymerization/one-pot hydrogenation is proposed. The structure of the reaction products was confirmed by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy (one-dimensional 1H and 13C spectra, two-dimensional homo- and heteronuclear correlation spectra 1H–1H COSY, 1H–13C multiplicity-edited HSQC, and 1H–13C H2BC) and by infrared (IR) spectroscopy. A technique for assignment of signals from protons and carbon atoms of heterodyads in the NMR spectra of the COE–ECOE copolymers was elaborated. Methods for calculating the average block lengths of comonomer units and the mole percentages of oxirane rings in the precursor unsaturated copolymers and in the hydrogenated products were developed. The synthesized products were studied by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and wide-angle X-ray diffraction (WAXD). Polarized optical microscopy was utilized to monitor the morphology and agglomeration behavior of paraffin crystals in diesel fuel blends. The effect of the synthesis and modification conditions on the molecular weight and on the thermal and crystalline properties was demonstrated. It was also shown that the hydrogenated COE–ECOE copolymers used as additives to diesel fuel decrease the cold filter plugging point of the resulting blends.