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    New organo soluble and thermally stable Schiff base polymers by oxidative polycondensation
    (ASIAN JOURNAL OF CHEMISTRY, 2008) Oezbuelbul, Asli; Tunel, Mehmet; Serin, Selahattin
    The Schiff base monomer was synthesized-by the condensation reaction between salicyladehyde and p-phenylendiamine. The Schiff base polymers having double azomethine group were prepared-by oxidative polycondensation (OP) reaction of monomer in aqueous alkaline medium with NaOCl (P-1) and H2O2 (P-2) as the oxidants at 90 degrees C. Cu(II) and Ni(II) complexes of the polymers. were synthesized by the reaction of polymer and metal acetate salts. The monomer and polymers; were characterized by elemental analyses, thermogravimetric analyses, DSC analyses, UV-Vis, FT-IR, H-1 and C-13 NMR spectroscopic studies, which revealed that the P and P-2 polymers synthesized by OP is composed of oxyphenylene (C-O-C; P-1 = 77% P-2 = 75%), phenylene (C-C; P, = 23%, P-2 = 25%) units. Average molecular weights of polymers were determined by gel permeation chromatography. The polymers were soluble in polar aprotic solvents and aqueous alkaline media. According to the thermogravimetric analyses, Schiff base polymer (P,) exhibited excellent thermal stability with 38% residual weight at 1000 degrees C in nitrogen atmosphere. The thermal stability of these polymer systems are found to be in order P-2 > P-1. As the synthesized polymers were soluble in common solvents such as THF, DMF, DMSO, these properties of polymer are-promising for it is environmental and analytical usage.
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    New soluble azophenol polymers prepared by oxidative polycondensation
    (WILEY, 2007) Canakci, Dilek; Tuncel, Mehmet; Mart, Hasan; Serin, Selahattin
    New azophenol polymers (P-1, P-2 and P-3) were synthesised by the oxidative polycondensation (OP) reaction of three different azophenol monomers in aqueous alkaline medium with NaOCl as the oxidant. The monomers and the polymers were characterised by elemental analyses, and UV-visible, Fourier transform infrared, H-1 NMR and C-13 NMR spectroscopic studies, which revealed that the polymers synthesised by OP are composed of oxyphenylene (C-O-C) and phenylene (C-C) units. The polymers obtained are soluble in dimethylformamide and dimethylsulfoxide. Average molecular weights of the polymers were determined by gel permeation chromatography. Additionally, P-2 and P-3 are soluble in water and methanol. On the basis of thermogravimetric analyses, 5 and 50% weight-loss temperatures of the polymers were found to be 218, 700 (P-1), 263, 609 (P-2) and 100, 809 degrees C (P-3), respectively, suggesting a high thermal stability. Thermal analyses using differential scanning calorimetry revealed that the azophenol polymers are highly amorphous, and melting peaks were not observed in the heating cycles. This suggests that all the polymers are highly amorphous. The azophenol polymers show a reversible trans-cis-trans isomerisation process. These properties of the polymer could be promising for their technological usage. (C) 2007 Society of Chemical Industry.