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    Synthesis and properties of novel Schiff base oligomers based on oligo-4-hydroxybenzaldehyde
    (JOHN WILEY & SONS INC, 2004) Mart, H; Sacak, M; Yuruk, H; Sahmetlioglu, E; Vilayetoglu, AR
    Condensation of oligo-4-hydroxybenzaldehyde with aniline, 2-chloroaniline, 2-aminophenol, 2-aminotoluene, 4-aminotoluene, and 4-nitroaniline gave the corresponding Schiff base oligomers (OFAP, OKAP, OHAP, OOAP, OTAP, and ONAP, respectively). The products were characterized by H-1 NMR, Fourier transform infrared, ultraviolet-visible, and elemental analyses. The number-average molecular weight, mass-average molecular weight, and polydispersity index (PDI) values of the Schiff base oligomers were determined. Thermogravimetric analysis was used to compare the thermal stability of the oligomers, which showed the Schiff base oligomers to be resistant to thermooxidative decomposition. Weight loss of 5% and 50% occurred at temperatures of 122 and 475 degreesC; for OFAP, at 118 and 453 degreesC; for OKAP, at 182 and 491 degreesC; for OHAP, at 150 and 452 degreesC; for OOAP, at 132 and 401 degreesC; for OTAP, and at 193 and 414 degreesC for ONAP. (C) 2004 Wiley Periodicals, Inc.
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    Synthesis, characterization and thermal degradation of some copper (II), zinc (II) and cobalt (II) complexes with oligosalicylaldehyde
    (ELSEVIER SCI LTD, 2004) Mart, H; Vilayetoglu, AR
    The complexes of copper (II), zinc (II) and cobalt (II) complexes with oligosalicylaldehyde (OSA) were synthesized. The oligomer metal complexes were characterized by FT-IR, magnetic moments and elemental analyses methods. Elemental analyses of oligomer-metal complexes suggest that the ratio of metal to oligomer is 1:2. The thermal stability of the oligomer-metal complexes was compared by thermogravimetric (TG) analyses. According to TG, oligomer-metal complexes were stable throughout to temperature and thermooxidative decomposition. The weight losses of oligomer-metal complexes were found to be 5 and 50% at 191 and 525 (Cu(II)), 300 and 592 (Zn(II)) and 245 and > 600 (Co(II)), degreesC, respectively. (C) 2003 Elsevier Ltd. All rights reserved.
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    The synthesis and properties of oligosalicylaldehyde and its Schiff base oligomers
    (ELSEVIER SCI LTD, 2001) Kaya, I; Vilayetoglu, AR; Mart, H
    The products and oxidative polycondensation reaction conditions of salicylaldehyde (SA) with air oxygen and sodium hypochloride (NaOCl) were studied. In this reaction, NaOCl was observed to be more active than O-2 and their optimum reaction conditions were determined. Oligosalicylaldehyde (OSA) was synthesized from the oxidative polycondensation of SA with air and NaOCl in an aqueous alkaline medium between 85 and 100 degreesC. The products were characterized by H-1-NMR, FT-IR, UV-Vis and elemental analysis. The number average molecular weight, mass average molecular weight and polydispersity index values of OSA synthesized at medium NaOCl and O-2 were found to be 3700, 5990 g mol(-1), 1.62 and 1690, 5150 g mol(-1), 3.05, respectively. At the optimum reaction conditions, the yield of the reaction products were found to be 65.5% (O-2) and 71.4% (NaOCl). About 80% SA was converted to OSA. TG analyses showed OSA to be resistant to thermo-oxidative decomposition. The weight loss of OSA were found to be 5, 50 and 89% at 217, 587 and 100 degreesC, respectively. Also, new oligomeric Schiff bases were synthesized from condensation of OSA with aniline, p-toluidine and p-nitroaniline and their the structures and properties were determined. (C) 2001 Elsevier Science Ltd. All rights reserved.
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    The synthesis, characterization and thermal stability of oligo-4-hydroxybenzaldehyde
    (ELSEVIER SCI LTD, 2004) Mart, H; Yuruk, H; Sacak, M; Muradoglu, V; Vilayetoglu, AR
    Oligo-4-hydroxybenzaldehyde (OHBA) was synthesized from the oxidative polycondensation of 4-hydroxybenzaldehyde (HBA) with hydrogenperoxide (H2O2) in an aqueous alkaline medium at 85 degreesC. The product was characterized by H-1 NMR, FT-IR, UV-Vis and elemental analysis. The number average molecular weight, mass average molecular weight and polydispersity index values of OHBA were found to be 5171, 8625 g mol(-1) and 1.668, respectively. The thermal stability of the oligomer was measured by thermogravimetric analyses (TG) under an air atmosphere. TG analyses showed OHBA to be resistant to thermo-oxidative decomposition. The weight loss of OHBA was found to be 5, 50 and 89% at 171, 845 and 900 degreesC, respectively. According to TG analyses, the carboneous residues of the OHBA was 49.29% at 900 degreesC. (C) 2003 Elsevier Ltd. All rights reserved.