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    Preparation of Poly (N-Isopropylacrylamide)-Poly (2-Ethyl-2-Oxazoline) and Their Self-Assembly Properties with Dicarboxylic Acid
    (Turkish Chemical Society, 2024) Yilmaz Erdogan P.; Emre F.B.; Seçkin T.
    This study reports the synthesis of copolymers that contain thermally responsive polymers, namely poly(N-isopropylacrylamide) (PNIPAM) and poly(2-ethyl-2-oxazoline) (PEOX), as well as biodegradable side groups that are water-soluble and capable of hydrogen bonding. The assay aims to produce heat-responsive PNIPAM and PEOX polymers with di-carboxylic acid (DCA) controlled structuring of the resulting pH-sensitive nano-structured polymers. These will be used as a template in the synthesis of inorganic materials. The study demonstrated the impact of pH, salt concentration, and temperature on the polymer/DCA. This fragment describes the functional groups of the thermosensitive polymers PNIPAM and PEOX. These polymers have carboxylic acid functional groups at both ends, are water soluble, and are capable of hydrogen bonding. The structure of these polymers can be recognized with small molecules of DCA in an aqueous solution at different pH, salt concentrations, and temperatures with H-bonds. Additionally, these polymers can be used as templates to synthesize hollow silica polymers. The synthesized monomers and polymers were structurally characterized using Fourier transform infrared spectrophotometer (FT-IR). The resulting structured polymers were identified by scanning electron microscopy and atomic force microscopy (SEM, AFM). UV-VIS spectrophotometer and Differential Scanning Calorimetry (DSC) were used to determine the Lower Critical Solution temperature of the polymers. © 2024, Turkish Chemical Society. All rights reserved.
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    Surface modification of inorganic oxide particles with a carbene complex of palladium: A recyclable catalyst for the Suzuki reaction
    (Springer New York LLC, 2004) Gürbüz N.; Özdemir I.; Seçkin T.; Çetinkaya B.
    The reaction of 1-(2,4,6-trimethylbenzyl)-3-(propyltriethoxysilane) imidazolidinium chloride, with the Pd(OAc)2 complex proceeded smoothly in DMSO to give the bis[1-(2,4,6-trimethylbenzyl)-3- (propyltriethoxysilane)imidazolidin-2-ylidene]dichloropalladium(II) complex that was grafted onto the surface of amorphous silica. The effects of various factors, such as reaction temperature and time, on the grafting efficiency was evaluated. Inorganic oxide particles that were modified with a carbene complex of palladium(II) were tested for catalytic activity in the Suzuki coupling reaction between phenylboronic acid and several aryl halides © 2004 Plenum Publishing Corporation.
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    Synthesis and characterization of polyimides prepared from optically active (R,R) and (S,S)-1,3-bis(p-N,N?-dimethylaminobenzyl)-perhydrobenzimidazol- 2-thion
    (2007) Yi?it M.; Seçkin T.; Köytepe S.; Çetinkaya E.
    This paper presents the synthesis and characterization of polyimides containing a chiral (R,R) or (S,S) 1,3-bis(p ? N,N?-dimethylaminobenzyl)- perhydrobenzimidazol-2-thion unit in the backbone. The reactions occur between equimolar amounts of a dianhydride and an aromatic dimethylamine in the presence of the solvent N-methyl-2-pyrollidone (NMP). In this work, the chiral monomer RR and SS -1,3-bis(p ? N,N?-dimethylaminobenzyl)-perhydrobenzimidazol-2- thion were used as diamines. The polyimides obtained were characterized by thermogravimetry (TGA), differential thermal analysis (DTA), differential scanning calorimeter (DSC), infrared spectroscopy (FT-IR), and gel permeation chromatography (GPC). It was found that the composition of the polymer had a significant effect upon the thermal behavior of the material. © TÜBİTAK.