Hazer, Baki | Hirao, Akira | Volga, Cüneyt
Article | 1999 | Macromolecular Chemistry and Physics200 ( 1 ) , pp.71 - 76
In order to synthesize benzoyl peroxide functionalized polystyrene (PSt), polyisoprene (PI) and poly(methyl methacrylate) (PMMA), anionic living PSt, PI, and PMMA were allowed to react with an excess amount of 4-(bromomethyl)benzoyl tert-butyl peroxide (BMtB) or bis[3,5-bis(bromomethyl)benzoyl] peroxide (BDBP) in tetrahydrofuran (THF) at -78°C. The results indicate that coupling reactions leading to dimers are significant during the reaction. Dimer formation was avoided when the living polystyrene was modified to the alcoholate anion by reaction with ethylene oxide (EO). © Wiley-VCH Verlag GmbH, 1999.
Hazer, Baki | Lenz, W. Lenz | Çakmaklı, Birten | Borcaklı, Mehlika | Koçer, Halil
Article | 1999 | Macromolecular Chemistry and Physics200 ( 8 ) , pp.1903 - 1907
Poly(3-hydroxyalkanoate)-g-poly(ethylene glycol) crosslinked graft copolymers are described. Poly(3-hydroxyalkanoate)s containing double bonds in the side chain (PHA-DB) were obtained by co-feeding Pseudomonas oleovorans with a mixture of nonanoic acid and anchovy (hamci) oily acid (in weight ratios of 50/50 and 70/30). PHA-DB was thermally grafted with a polyazoester synthesized by the reaction of poly(ethylene glycol) with MW of 400 (PEG-400) and 4,4'-azobis(4-cyanopentanoyl chloride). Sol-gel analysis and spectrometric and thermal characterization of the networks are reported. © Wiley-VCH Verlag GmbH, 1999.
Arslan, Hülya | Hazer, Baki
Article | 1999 | European Polymer Journal35 ( 8 ) , pp.1451 - 1455
Polymerization of methyl methacrylate (MMA) initiated by ceric ammonium nitrate in combination with polytetrahydrofuran diol (PTHF-diol) and polycaprolactone diol (PCL-diol) has been investigated in aqueous nitric acid. PMMA-b-PTHF and PMMA-b-PCL block copolymers were obtained. Block copolymer yield was increased when using tetrabutyl ammonium hydrogen sulphate as a surfactant. The effects of nitric acid and eeric ions on the block copolymer yields were investigated. Block copolymers were characterized using GPC, 1 H-NMR, DSC, TGA and fractional precipitation methods. © 1999 Elsevier Science Ltd. All rights reserved.
Arslan, Hülya | Adamus, Grażyna | Hazer, Baki | Kowalczuk, Marek
Article | 1999 | Rapid Communications in Mass Spectrometry13 ( 24 ) , pp.2433 - 2438
Evaluation of polymer end-capping reactions with the aid of electrospray ionisation tandem mass spectrometry techniques (ESI-MS(n)) allows characterisation of novel poly[(R,S)-3-hydroxybutanoic acid] (a-PHB) telechelics, containing primary hydroxyl groups at both polymer chain ends. The chemical structures of individual mass-selected macromolecules of the well-defined a-PHB telechelics haze been defined in this way, and fragmentation mechanisms have been proposed.
Wu, Bin | Lenz, Robert W. | Hazer, Baki
Article | 1999 | MACROMOLECULES32 ( 20 ) , pp.6856 - 6859
Yıldız, Ufuk | Hazer, Baki
Article | 1999 | Angewandte Makromolekulare Chemie265 , pp.16 - 19
The free radical dispersion polymerization of styrene (St) and methyl methacrylate (MMA) initiated by poly(oxyethylene) (PEO) macroazoinimer (MIM-400) in water/ethanol, was investigated at three different temperatures (50, 60 and 80°C) for seven polymerization times (3, 6, 9, 12, 24, 36 and 48 h). PSt-PEO and PMMA-PEO networks were obtained. In each case, polymer gel fractions depend on the polymerization temperature and polymerization time. With the same initial concentration of MIM-400, maximum gel fraction was found at 80 wt.-% with St copolymerization while 100 wt.-% in case of copolymerization with MMA at 80°C for 48 h. © Wiley . . .-VCH Verlag GmbH, 1999 Daha fazlası Daha az