Çakmaklı, Birten | Hazer, Baki | Tekin, İshak Özel | Cömert-Beğendik, Füsun

Article | 2005 | Biomacromolecules6 ( 3 ) , pp.1750 - 1758

Peroxidation, epoxidation, and/or perepoxidation reactions of soybean oil under air at room temperature resulted in cross-linked polymeric soybean oil peroxides on the surface along with the waxy soluble part, sPSB, with a molecular weight of 4690, containing up to 2.3 wt % peroxide. This soluble polymeric oil peroxide, sPSB, initiated the free radical polymerization of either methyl methacrylate (MMA) or n-butyl methacrylate (nBMA) to give PSB-g-PMMA and PSB-g-PnBMA graft copolymers. The polymers obtained were characterized by 1H NMR, thermogravimetric analysis, differential scanning calorimetry, and gel permeation chromatography t . . .echniques. Polymeric oil as a plasticizer lowered the glass transition of the PSB-g-PMMA graft copolymers. PSB-g-PMMA and PSB-g-PnBMA graft copolymer film samples were also used in cell culture studies. Fibroblast and macrophage cells were strongly adhered and spread on the copolymer film surfaces, which is important in tissue engineering. Bacterial adhesion on PSB-g-PMMA graft copolymer was also studied. Both Staphylococcus epidermidis and Escherichia coli adhered on the graft copolymer better than on homo-PMMA. Furthermore, the latter adhered much better than the former. © 2005 American Chemical Society Daha fazlası Daha az

Hazer, Baki | Akyol, Elvan | Şanal, Timur | Guillaume, Sophie | Çakmaklı, Birten | Steinbuchel, Alexander

Article | 2019 | Polymer Bulletin76 ( 2 ) , pp.919 - 932

Poly(3-hydroxyalkanoate)s (PHAs) are a class of polymers receiving attention because of their potential as renewable, biodegradable and high-technology properties. Unlike most short chain length (scl) PHAs such as poly(3-hydroxybutyrate) (PHB), medium chain length (mcl) PHAs such as poly(3-hydroxyoctanoate) (PHO) exhibit low crystallinity and are elastomeric in character. PHB-b–PEG-b–PHO block copolymers can combine both properties in block copolymer matrix. In this study, we report the synthesis of the block copolymers combining the PHB and PHO blocks. Transamidation reactions of PHB with polyethylene glycol with primary amine yiel . . .d equimolar amounts and PHB with amine ends. PHO reacts with the modified PHB containing the amine end to give PHB-b–PEG-b–PHO block copolymers. Structural analysis of the products was performed by using 1H–, 13C, heteronuclear single quantum coherence NMR techniques. Thermal and mechanical properties of the block polymers were also evaluated. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature Daha fazlası Daha az

Çakmaklı, Birten | Hazer, Baki | Tekin, İshak Özel | Açıkgöz, Şerefden | Can, Murat

Article | 2007 | JAOCS, Journal of the American Oil Chemists' Society84 ( 1 ) , pp.73 - 81

To diversify edible-oil polymer composite, polymeric linoleic acid (PLina) peroxide was obtained by the auto-oxidation of linoleic acid in a simple way for use as a macroinitiator in free radical polymerization of vinyl monomers. Peroxidation, epoxidation, and/or perepoxidation reactions of linoleic acid under air at room temperature resulted in PLina, having soluble fraction more than 91 weight percent (wt%), with molecular weight ranging from 1,644 to 2,763 Da, and containing up to 1.0 wt% of peroxide. PLina initiated the free radical polymerization of ether styrene (S), methyl methacrylate (MMA), or n-butyl methacrylate (nBMA) to . . . give PLina-g-polystyrene (PS), PLina-g-poly-MMA (PMMA), and PLina-g-poly- nBMA (PnBMA) graft copolymers. The polymers obtained were characterized by proton nuclear magnetic resonance (1H NMR), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and gel permeation chromatography (GPC) techniques. Microstructure of the graft copolymers was observed by using scanning electron microscope (SEM). Graft copolymers obtained contained polymeric linoleic acid in a range between 8.5 and 19.3 mol percent (mol%). PLina-g-PS, PLina-g-PMMA and PLina-g-PnBMA graft copolymer samples were also used in cell culture studies. Fibroblast and macrophage cells were strongly adhered and spread on the copolymer film surfaces. These newly synthesized copolymers were tested for their effects on human blood protein adsorption compared with PMMA graft copolymers containing polymeric soybean oil and polymeric linseed oil; interestingly we observed a dramatic decrease in the protein adsorption on the linoleic acid graft copolymer, which is important in tissue engineering. © AOCS 2007 Daha fazlası Daha az

Çakmaklı, Birten | Hazer, Baki | Borcaklı, Mehlika

Article | 2001 | Macromolecular Chemistry and Physics202 ( 16 ) , pp.348 - 354

A new soluble terephthaloyl oligoperoxide (OTP) was synthesized by the reaction of terephthaloyl. peroxide and 2,5-dimethyl 2,5-dihydroperoxy hexane. Thermal polymerization of vinyl monomers (styrene, methyl methacrylate) with OTP yielded poly(styrene peroxide) (PS-P) and poly(methyl methacrylate peroxide) (PMMA-P) which are used in the grafting reactions onto medium chain length unsaturated bacterial polyester obtained from soybean oily acids with Pseudomonas oleovorans poly(3-hydroxy alkanoate), (PHA). PS-g-PHA and PMMA-g-PHA graft copolymers isolated from related homopolymers were characterizated by 1H NMR spectrometry, FT-IR spe . . .ctroscopy, thermal analysis and gel permeation chromatographic (GPC) techiques. Swelling measurement of the crosslinked graft copolymers were also measured to calculate qv values Daha fazlası Daha az

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.

Kızılçay, Ebru | Çakmaklı, Birten | Hazer, Baki | Denkbaş, Emir Baki | Açikgöz, Bektaş

Article | 2011 | Journal of Applied Polymer Science119 ( 3 ) , pp.1610 - 1618

Poly(methyl methacrylate) (PMMA) and PMMA copolymers derived from plant oils (Polylinseed oil-g-PMMA, Polysoybean oil-g-PMMA, Polylinoleic acid-g-PMMA (PLina-g-PMMA) and Polyhydroxy alkanoate- sy-g-Polylinoleic acid-g-PMMA (PHA-g-PLina-g-PMMA)) as hydrophobic polymers, a series of hydrophobic microsphere or nanosphere dispersions, were prepared by the emulsion/solvent evaporation method. The diameters of the nanospheres and microspheres were measured by dynamic light scattering with a zetasizer, optically and by scanning electron microscopy. The magnetic quality of the microspheres was determined by the electron spin resonance techn . . .ique. Acetylsalicylic acid (aspirin, ASA) was used as a model drug and loaded into the microspheres during the preparation process. The effect of the stirring rate over the size and size distribution of the micro/nanospheres was evaluated, and the effects of copolymer types derived from plant oil/oily acids and the copolymer/drug ratios were evaluated. © 2010 Wiley Periodicals, Inc Daha fazlası Daha az

Çakmaklı, Birten | Hazer, Baki | Erdoğan, Taner | Mutlu, Ayşe Gül

Article | 2013 | Journal of Polymer Research20 ( 3 ) , pp.1610 - 1618

A variety of new polymeric materials [Polylinseed oil-g-PMMA (PLO-g-PMMA), Polylinseed oil-g-PS (PLO-g-PS), Polysoybean oil-g-PMMA (PSB-g-PMMA), Polylinoleic acid-g-PMMA (PLina-g-PMMA), Polylinoleic acid-g-PS (PLina-g-PS), Polylinoleic acid-g-PnBMA (PLina-g-PnBMA), Polyhydroxy alkanoate-sy-g- Polysoybean oil-g-PMMA (PHA-PSB-PMMA) and Polyhydroxy alkanoate-sy-g- Polylinoleic acid-g-PMMA (PHA-PLina-PMMA)] were prepared from soluble polymeric oil/oily acid peroxides initiating the co-polymerization of Poly(methyl methacrylate) (PMMA), Polystyrene (PS) and Poly(n-butyl methacrylate) (PnBMA). Pure PMMA, PS, PnBMA and these copolymers con . . .tain different polymeric oil/oil acid initiators were investigated as to the relationship between their dynamic mechanical properties. The DMA results show that the transition from glassy to rubbery behavior is broad for these polymers due to the presence of the triglyceride/oil acid molecules acting like plasticizers in the system. Furthermore, they were compared with dynamic mechanical analysis (DMA) and differential scanning calorimeter (DSC) analysis results. The mechanical properties of these homopolymer and copolymers were also assessed by tensile tests of the polymers in terms of the stress and strain values at the break point. When these results were compared with those for PMMA and PnBMA, it is worth noting that copolymer samples containing PLO, PSB, or PLina in its structure showed changed stress at their break point or in the strain value at its break point. The contact angle testing and DNA adsorption of oil/oil acid copolymers were also studied. Compared with homopolymers, the hydrophilicity and DNA adsorption of the copolymer samples improved because of the presence of PLO, PSB, or PLina blocks. Considering all these results, it is recommended that the copolymers used as candidate biomaterials. © 2013 Springer Science+Business Media Dordrecht Daha fazlası Daha az

Çakmaklı, Birten | Hazer, Baki | Açıkgöz, Şerefden | Can, Murat | Cömert, Füsun B.

Article | 2007 | Journal of Applied Polymer Science105 ( 6 ) , pp.3448 - 3457

Synthesis of Poly(methyl methacrylate), PMMA-multigraft copolymers derived from linseed oil, soybean oil, and linoleic acid PMMA-g-polymeric oil/oily acid-g-poly(3-hydroxy alkanoate) (PHA), and their protein adsorption and bacterial adherence have been described. Polymeric oil/oily acid peroxides [polymeric soybean oil peroxide (PSB), polymeric linseed oil peroxide (PLO), and polymeric linoleic acid peroxide (PLina)] initiated the copolymerization of MMA and unsaturated PHA-soya to yield PMMA-PLO-PHA, PMMA-PSB-PHA, and PMMA-PLina-PHA multigraft copolymers. PMMA-PLina-PHA multigraft copolymers were completely soluble while PMMA-PSB-P . . .HA and PMMA-PLO-PHA multigraft copolymers were partially crosslinked. Crosslinked parts of the PLO- and PSB-multigraft copolymers were isolated by the sol gel analysis and characterized by swelling measurements in CHCl3. Soluble part of the PLO- and PSB-multigraft copolymers and completely soluble PLina-multigraft copolymers were obtained and characterized by spectroscopic, thermal, gel permeation chromatography (GPC), and scanning electron microscopy (SEM) techniques. In the mechanical properties of the PHA-PLina-PMMA, the elongation at break is reduced up to ~ 9%, more or less preserving the high stress values at its break point (48%) when compared to PLina-g-PMMA. The solvent casting film surfaces were studied by means of adsorption of blood proteins and bacterial adhesion. Insertion of the PHA into the multigraft copolymers caused the dramatic increase in bacterial adhesion on the polymer surfaces. PHA insertion into the graft copolymers also increased the protein adsorption. © 2007 Wiley Periodicals. Inc Daha fazlası Daha az

Çakmaklı, Birten | Hazer, Baki | Tekin, İshak Özel | Kızgut, Sait | Köksal, Murat | Menceloğlu, Yusuf

Article | 2004 | Macromolecular Bioscience4 ( 7 ) , pp.649 - 655

Syntheses of wholly natural polymeric linseed oil (PLO) containing peroxide groups have been reported. Peroxidation, epoxidation and/or perepoxidation reactions of linseed oil, either under air or under oxygen flow at room temperature, resulted in polymeric peroxides, PLO-air and PLO-ofl, containing 1.3 and 3.5 wt.-% of peroxide, with molecular weights of 2 100 and 3 780 Da, respectively. PLO-air contained cross-linked film up to 46.1 wt.-% after a reaction time of 60 d, associated with a waxy, soluble part (PLO-air-s) that was isolated with chloroform extraction. PLO-ofl was obtained as a waxy, viscous liquid without any cross-link . . .ed part at the end of 24 d under visible irradiation and oxygen flow. Polymeric peroxides, PLO-air-s and PLO-ofl initiated the free radical polymerization of both methyl methacrylate (MMA) and styrene (S) to give PMMA-graft-PLO and PS-graft-PLO graft copolymers in high yields with Mw varying from 37 to 470 kDa. The polymers obtained were characterized by FT-IR, 1H NMR, TGA, DSC and GPC techniques. Cross-linked polymers were also studied by means of swelling measurements. PMMA-graft-PLO graft copolymer film samples were also used in cell-culture studies. Fibroblast cells were well adhered and proliferated on the copolymer film surfaces, which is important in tissue engineering Daha fazlası Daha az