Preparation and characterization of cycloolefin polymer based on dicyclopentadiene (DCPD) and dimethanooctahydronaphthalene (DMON)

Ring-opening metathesis polymerization (ROMP) and subsequent hydrogenation of the mixture of dicyclopentadiene (DCPD) and 1,4,5,8-dimethano-1,2,3,4,4a,5,8,8a-octahydronaphthalene (DMON) were conducted. ROMP was successfully performed at room temperature using WCl6/iBu3Al/2-BuOH (1/0.7/1.2) catalyst system when the DCPD/DMON molar ratio was 1. Depending on the DCPD/DMON molar ratio, the catalyst component ratio for the polymerization changed. The double bond in the prepared ROMP polymer could be completely hydrogenated using Ni(acac)2/iBu3Al at molar ratio of the Ni/double bond in polymer = 0.2 mol% and Al/Ni = 4 when the reaction was conducted at 80 °C for 3 h. After hydrogenation, the glass transition temperature (Tg) of all ROMP polymers was decreased by 40 °C. Depending on the DCPD and DMON molar ratio, the Tg of the ROMP polymer and hydrogenated ROMP polymer changed. The hydrogenated DCPD–DMON ROMP copolymer was characterized by using 2D 1H–1H COSY and 2D 1H–13C HSQC NMR spectroscopy. Thermal stability and light transmittance for the ROMP polymer and the hydrogenated ROMP polymer were compared by using TGA and UV.