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    Electrochemical polymerization of 4-allyl-1,2-dimethoxybenzene
    (Elsevier Science Bv, 2004) Testereci, HN; Akin-Oktem, G; Oktem, Z
    Redox behaviour of 4-allyl-1,2-dimethoxybenzene (DMAB) was studied by using cyclic voltammetry and electro-chemical polymerization was conducted at the measured peak potential. Constant potential electrolysis of the monomer was carried out in acetonitrile-tetrabutylammonium-tetrafluoroborate, solvent-electrolyte couple, at room temperature. Electrochemical polymerization of the monomer yielded insoluble polymer film on the electrode surface together with the low molecular weight polymers in bulk of the solution. The effect of temperature on the rate of electro-chemical polymerization was also studied. The structural analyses of the polymers were done by H-1-NMR and FTIR spectroscopy. Molecular weight of the soluble polymer was determined by cryoscopy. (C) 2004 Elsevier B.V. All rights reserved.
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    Functionalization of low molecular weight atactic polypropylene - Part I. Spectroscopic studies
    (Springer Verlag, 1999) Oktem, Z; Cetin, S; Akin-Oktem, G
    Low molecular weight atactic polypropylene (APP) was functionalized with 4-allyl-2-methoxyphenol (eugenol), 4-allyl-1,2-dimethoxybenzene (DMAB), 4-propenylanisole(trans-anethole), cis-2,4,5-trimethoxypropenylbenzene (beta-asarone) and 4-allyl-2,6-dimethoxyphenol (ADMP) in the presence of dicumyl peroxide (DCP) at 170 degrees C. Amount of grafted eugenol, DMAB and anethole on APP and characterization of the products were carried by UV-VIS and FTIR spectroscopies respectively. The effects of the reaction time, concentrations of the functional compounds and DCP on the extent of grafting were examined.
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    Functionalization of low molecular weight atactic polypropylene - Part II. Thermal and molecular weight studies
    (Springer, 2000) Akin-Oktem, G; Cetin, S; Oktem, Z
    Number average molecular weight (M-n), intrinsic viscosity ([eta]) and glass transition temperature (T-g) of low molecular weight atactic polypropylene (APP) grafted with 4-allyl-1,2-dimethoxybenzene (DMAB), 4-allyl-2-methoxyphenol (eugenol) and 4-propenylanisole (trans-anethole) in the presence of dicumyl peroxide (DCP) at 170 degreesC were determined. The influences of reaction time, concentration and extent of grafting on M-n, [eta] and T-g of APP were examined. The data were discussed with the mechanism of grafting reactions.
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    Novel hydrophobic ligand-containing hydrogel membrane matrix: preparation and application to gamma-globulins adsorption
    (Elsevier Science Bv, 2001) Arica, MY; Akin-Oktem, G; Denizli, A
    In this study, phenylalanine as a hydrophobic ligand was covalently attached to the co-monomer methacrylochloride. Then, poly(2-hydroxyethylmethacrylate-co-methacrylamidophenyalanine) [poly(HEMA-MApA)] membranes were prepared by UV-initiated photopolymerization of HEMA and methacrylamidophenyalanine. The gamma -globulins adsorption onto these affinity membranes from aqueous solutions containing different amounts of gamma -globulins at different pH was investigated in a batch system. The gamma -globulins adsorption capacity of the membranes was increased as the ligand density on the membrane surface increase. The non-specific adsorption of the gamma -globulins on the pHEMA membranes was negligible. The adsorption phenomena appeared to follow a typical Langmuir isotherm. The maximum adsorption capacity (q(m)) of the poly(HEMA-MAPA4) membrane for gamma -globulins was 2.37 mg g(-1) dry membrane. The equilibrium constant (k(d)) value was found to be 1.61 x 10(-1) mg ml(-1). More than 87% (up to 100%) of the adsorbed gamma -globulins were desorbed in 120 min in the desorption medium containing 50% ethylene glycol in 1.0 M NaCl. (C) 2001 Elsevier Science B.V. All rights reserved.