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    Application of well-defined ruthenium alkylidenes to the ROMP of norbornene derivatives: Methoxyphenyl-substituted polynorbornene dicarboximides
    (Elsevier Science Bv, 2011) Cetinkaya, Sevil; Ozker, Taner; Bayram, Rifat
    The applicability of ruthenium alkylidenes as initiators in the ring opening metathesis polymerization (ROMP) of methoxyphenyl group containing norbornene derivatives has been investigated. The synthesis and polymerization of exo-N-4-methoxyphenyl-oxanorbornene-5,6-dicarboximide (MeOPhONDI) and exo-N-4-methoxyphenyl-norbornene-5,6-dicarboximide (MeOPhNDI) are reported. Polynorbornene derivatives were obtained via ROMP using first- and second-generation ruthenium alkylidene initiators. The structural properties of the polynorbornene derivatives were analyzed by NMR, DSC and GPC. Analyses of the polymer microstructures indicate that polymers contain trans stereoconfiguration of the double bonds (55-86% trans-content). The glass transition temperatures of the polymers obtained from exo-monomers are higher than 211 degrees C. (C) 2010 Elsevier B.V. All rights reserved.
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    Highly porous NiO/poly(DVB)HIPE nanocomposites for asphaltene removal: synthesis, kinetics, and thermodynamic studies
    (Springer, 2019) Ozker, Taner; Cetinkaya, Sevil
    Asphaltene precipitation is one of the most important problems of the petroleum industry. Asphaltene collapses during petroleum processing and extraction from the well, blocking the pipes and causing many problems. For this reason, asphaltene should be removed from heavy crude oils to improve the quality of oil and prevent asphaltene deposition. In this study, for the first time, highly porous new polyHIPE nanocomposites containing NiO nanoparticles (NPs) have been prepared for asphaltene removal. The open-celled new poly(DVB)HIPE nanocomposites were synthesized by the polymerization of monomers in the external phase of water-in-oil emulsions containing NiO NPs in the organic phase. The highest surface area was obtained at 5 wt% of NiO NP loading (367 m(2)/g). The adsorption of asphaltenes from toluene solutions onto NiO/poly(DVB)HIPE nanocomposite was investigated in detail. Maximum adsorption was obtained as 384.6 mg/g at a temperature of 298 K for NiO/poly(DVB)HIPE nanocomposite. The Freundlich, Langmuir, and Temkin isotherm models were used to correlate the adsorption data of asphaltenes on NiO/poly(DVB)HIPE nanocomposite and adsorption constants of these models were calculated. The Freundlich and Langmuir gave better results at different temperatures. The pseudo-second-order kinetic model provided the best correlation with the experimental data (R-2 >= 0.997). The results of the thermodynamic experiments showed that the adsorption was spontaneous and exothermic. It is concluded that the polyHIPE nanocomposites are important for the oil industry owing to having potential use as an adsorbent.
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    Influence of ruthenium alkylidene complexes bearing tricyclohexylphosphine or 3-bromopyridine ligand on the properties of fluorine containing polymers
    (Springer, 2013) Cetinkaya, Sevil; Ozker, Taner; Kaya, Pembe Hulya; Yasar, Emine; Bayram, Rifat
    The catalytic performance of ruthenium alkylidene complexes bearing tricyclohexylphosphine or 3-bromopyridine ligand in the ring opening metathesis polymerization (ROMP) of fluorine containing monomers, exo-N-4-fluorophenyl-7-oxanorbornene-5,6-dicarboximide (FPhONDI) and exo-N-4-fluorophenyl-norbornene-5,6-dicarboximide (FPhNDI) was investigated. Pure monomers were subjected to ROMP with RuCl2(PCy3)(2)(CHPh) (I), RuCl2(PCy3)(H(2)IMes)(CHPh) (II), RuCl2(3-Br-py)(2)(PCy3)(CHPh) (III) and RuCl2(3-Br-py)(2)(H(2)IMes)(CHPh) (IV). The polymers were fully characterized using NMR, DSC, SEM and GPC. Catalysts I-IV displayed significant ROMP activity, allowing for the synthesis of the corresponding polymers with polydispersity indices (PDIs) in the range of 1.4-4.0. High molecular weight polymers (Mw up to 4.95 x10(5)) were prepared in yields up to 90 %, depending on the initiator and monomer used.
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    Preparation and characterization of new nanocomposite polymer films containing NiO nanofillers
    (Wiley, 2018) Cetinkaya, Sevil; Sonmez, Damla; Ozker, Taner
    Nanocomposite solid polymer films based on the poly(exo-N-phenyl-7-oxanorbornene-5,6-dicarboximide) (PPhONDI)/LiClO4/NiO system have been designed, and the effect of inorganic NiO nanofiller in different amounts on the film properties has been examined. The exo-PPhONDI/LiClO4/NiO polymer system is the first solid nanocomposite polymer electrolyte film example based on a ring-opening metathesis polymerization (ROMP) host polymer. The NiO nanoparticles were prepared by two-step chemical syntheses, and the thermoplastic host polymer, exo-PPhONDI, was synthesized via ROMP. Composite polymer films were prepared by the solution-casting method. The amount of nanoparticles was varied from 1 to 15wt % of NiO. The conductivity of the nanocomposite solid polymer systems was influenced by the NiO nanofiller concentration. The composite films based on exo-PPhONDI ROMP polymer with the highest conductivity were achieved for the composition with 8 wt % of NiO nanofiller and 10 wt % of LiClO4 dopant. The prepared films were characterized using X-ray diffraction, Fourier transform infrared spectroscopy, differential scanning calorimetry, and scanning electron microscopy (SEM). The SEM results showed that the filler was well distributed in the polymer matrix. (c) 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45938.