Macit, Hülya | Hazer, Baki | Arslan, Hülya | Noda, Isao

Article | 2009 | Journal of Applied Polymer Science111 ( 5 ) , pp.2308 - 2317

A new and promising method for the diversification of microbial polyesters based on chemical modifications is introduced. Poly(3-hydroxy alkanoate)-g-(poly(tetrahydrofuran)-b-poly(methyl methacrylate)) (PHAg-(PTHF-b-PMMA)) multigraft copolymers were synthesized by the combination of cationic and free radical polymerization. PHA-g-PTHF graft copolymer was obtained by the cationic polymerization of THF initiated by the carbonium cations generated from the chlorinated PHAs, poly(3-hydroxybutyrate-co-3- hydroxyvalerate) (PHBV), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHx) in the presence of AgSbF 6. Therefore, PHA-g-PTHF gr . . .aft copolymers with hydroxyl ends were produced. In the presence of Ce +4 salt, these hydroxyl ends of the graft copolymer can initiate the redox polymerization of MMA to obtain PHA-g-(PTHF-b-PMMA) multigraft copolymer. Polymers obtained were purified by fractional precipitation. In this manner, their ?-values (volume ratio of nonsolvent to the solvent) were also determined. Their molecular weights were determined by GPC technique. The structures were elucidated using 1H-NMR and FTIR spectroscopy. Thermal analyses of the products were carried out using differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA). © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 111: 2308-2317, 2009 Daha fazlası Daha az

Kolsal, Ebru | Tekin, İshak Özel | Pişkin, Etem | Aydemir, Cumhur | Akyüz, Mehmet | Çabuk, Hasan | Eldes, Nilüfer | Numanoğlu, Kemal Varın

Article | 2009 | Journal of Clinical Apheresis24 ( 1 ) , pp.21 - 24

Tricyclic antidepressant poisoning is one of the most common causes of serious intoxication. Here, we report a 2-year-old girl with severe amitriptyline (70 mg/kg) intoxication. She was in comatose, had generalized tonic clonic seizure, ventricular tachycardia, and wide QRS complexes. Although she did not respond to classical therapies, very good clinical response to plasmapheresis was obtained and she developed no complications. Thus, plasmapheresis may be an effective treatment modality in poisoning with drugs, which bind to plasma proteins with high affinity. © 2009 Wiley-Liss, Inc.

Keleş, Elif | Hazer, Baki

Article | 2009 | Journal of Polymers and the Environment17 ( 3 ) , pp.153 - 158

Polyurethane (PUR) plastic sheets were prepared by reacting hydroxylated polymeric soybean oil (PSbOH) synthesized from autoxidized soybean oil with polyethylene glycol (PEG) in the presence of isophorone diisocyanate (IPDI). FTIR technique was used to identify of chemical reactions. These polyurethanes have different valuable properties, determined by their chemical composition. The effect of stoichiometric balance (i.e., PSbOH/PEG-2000/IPDI weight ratio) on the final properties was evaluated. The polyurethane plastic sheets with the PSbOH/PEG-2000/IPDI weight ratio 1.0/1.0/0.67 and 1.0/0.3/0.3 had excellent mechanical properties i . . .ndicating elongation at break more than 200%. Increase in IPDI and decrease in PEG weight ratio cause the higher stress-strain value. The properties of the materials were measured by differential scanning calorimetry (DSC), thermo gravimetric analysis (TGA), stress-strain measurements and FTIR technique. © 2009 Springer Science+Business Media, LLC Daha fazlası Daha az

Hazer, Derya Burcu | Hazer, Baki | Kaymaz, Figen

Article | 2009 | Biomedical Materials4 ( 3 ) , pp.153 - 158

Biocompatibility studies of the autoxidized and unoxidized unsaturated medium-long chain length (m-lcl) co-poly-3-hydroxyalkanoates (m-lclPHAs) derived from soya oily acids have been reported. Pseudomonas oleovorans was grown on a series of mixtures of octanoic acid (OA) and soya oily acids (Sy) with weight ratios of 20:80, 28:72 and 50:50 in order to obtain unsaturated m-lcl copolyesters coded PHO-Sy-2080, PHO-Sy-2872 and PHO-Sy-5050, respectively. The PHA films were obtained by solvent cast from CHCl3. They were all originally sticky and waxy except PHO-Sy-5050. Autoxidation of the unsaturated copolyester films was carried out on . . .exposure to air at room temperature in order to obtain crosslinked polymers. They became a highly flexible elastomer after being autoxidized (about 40 days of autoxidation). The in vivo tissue reactions of the autoxidized PHAs were evaluated by subcutaneous implantation in rats. The rats appeared to be healthy throughout the implantation period. No symptom such as necrosis, abscess or tumorigenesis was observed in the vicinity of the implants. Retrieved materials varied in their physical appearance after 6 weeks of implantation. In vivo biocompatibility studies of the medical applications indicated that the microbial copolyesters obtained were all biocompatible and especially the PHOSy series of copolyesters had the highest biocompatibility among them. © 2009 IOP Publishing Ltd Daha fazlası Daha az

Allı, Abdulkadir | Hazer, Baki

Article | 2009 | Hacettepe Journal of Biology and Chemistry37 ( 1 ) , pp.23 - 31

A new macromonomer initiator for atom transfer radical polymerization (ATRP-MIM) based on polyethylene glycol (Mn= 660 Da) (PEG) was synthesized by the reaction of hydroxyl end of the mono-methacryloyl polyethylene glycol with 2-bromopropanoyl chloride leading to methacryloyl polyethylene glycol 2-bromopropanoyl ester (v-PEG-Br). Poly(ethylene glycol) functionalized with methacrylate at one end was reacted with 2-bromopropionyl chloride to form a macromonomeric initiator for ATRP. Self condensing ATRP-MIM polymerization yielded branched PEG with low cross-linked fraction (3-29 wt%). In the same polymerization condition, self condens . . .ing ATRP-MIM polymerization was found faster than that of conventional free radical macromonomer initiators which behave as macro crosslinker, macro initiator and macromonomer. Besides the PEG obtained has still unreacted double bonds and halides leading to the further branching. In the second step, ATRP of methyl methacrylate was initiated by the MIM-ATRP using the copper coordination complex CuBr / N,N,N’,N’,N’’-pentamethyl diethylenetriamine (PMDETA). The ATRP-MIM and the chloroform soluble branched polymers obtained were characterized by 1H NMR spectroscopy and gel permeation chromatography (GPC). Variation of gel polymer content, molecular weight of the soluble parts and conversion of the monomers with the changing polymerization conditions were also discussed. A new macromonomer initiator for atom transfer radical polymerization (ATRP-MIM) based on polyethylene glycol (Mn= 660 Da) (PEG) was synthesized by the reaction of hydroxyl end of the mono-methacryloyl polyethylene glycol with 2-bromopropanoyl chloride leading to methacryloyl polyethylene glycol 2-bromopropanoyl ester (v-PEG-Br). Poly(ethylene glycol) functionalized with methacrylate at one end was reacted with 2-bromopropionyl chloride to form a macromonomeric initiator for ATRP. Self condensing ATRP-MIM polymerization yielded branched PEG with low cross-linked fraction (3-29 wt%). In the same polymerization condition, self condensing ATRP-MIM polymerization was found faster than that of conventional free radical macromonomer initiators which behave as macro crosslinker, macro initiator and macromonomer. Besides the PEG obtained has still unreacted double bonds and halides leading to the further branching. In the second step, ATRP of methyl methacrylate was initiated by the MIM-ATRP using the copper coordination complex CuBr / N,N,N’,N’,N’’-pentamethyl diethylenetriamine (PMDETA). The ATRP-MIM and the chloroform soluble branched polymers obtained were characterized by 1H NMR spectroscopy and gel permeation chromatography (GPC). Variation of gel polymer content, molecular weight of the soluble parts and conversion of the monomers with the changing polymerization conditions were also discussed Daha fazlası Daha az

Allı, Abdulkadir | Hazer, Baki

Proceedings | 2009 | ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY237 , pp.23 - 31

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