Yazar "Icduygu, MG" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim Yok
    Öğe
    Preparation and characterization of polybenzimidazole-clay hybrid materials
    (Elsevier Science Sa, 2004) Gültek, A; Icduygu, MG; Seçkin, T
    Thermally stable bentonite-polybenzimidazole (PBI) nanocomposites were synthesized from reactive organoclay and polybenzimidazole. The reactive organoclay was formed by using hexadecylpyridinium chloride (CPC) as a swelling agent for silicate layers of bentonite. The swelling process was carried out through ion exchange reaction between the end group of hexadecylpyridinium chloride salt and the sodium ion in bentonite. This irreversible swelling monitored by measuring the cation exchange capacity (CEC) of the bentonite solutions. Dispersion of the modified clay in the polybenzimidazole matrix resulted in nanostructured material containing intercalated polymer between the silicate layers. X-ray and thermal analysis confirmed structure of the now hybrid materials. The glass transition temperature and the thermal decomposition temperatures of this type bentonite-PBI were found to be higher than that of pure PBI. (C) 2003 Elsevier B.V. All rights reserved.
  • Küçük Resim Yok
    Öğe
    Preparation and phenol captivating properties of polyvinylpyrrolidone-montmorillonite hybrid materials
    (Wiley, 2001) Gultek, A; Seckin, T; Onal, Y; Icduygu, MG
    Montmorillonite minerals were modified in two distinct steps in order to remove hydroxlated toxicants from the aqueous environment. At first, the montmorillonite minerals were acrylated with the silylating agent gamma -methcaryloxypropyl trimethoxysilane to give a product denoted as TAY-10. In the second step these materials readily reacted with vinylpyrrolidone to form copolymers covalently bonded to the clay. All hybrid materials were characterized by FTIR spectroscopy, thermogravimetry, X-ray diffractometry, SEM, and differential thermal analysis. The original montmorillonite structure was maintained for the copolymer modified surfaces. Different loadings of polyvinylpyrrolidone (PVP) were examined to arrive at the optimal conditions for the removal of toxicants from the aqueous environment. The presence of the PVP enhanced the adsorption capacity of the clay toward phenolic compounds from solution as evidenced by the retention percent that was as high as 98.9%. These results demonstrated the feasibility of utilizing a PVP modified clay as a thermally recyclable adsorbent for environmental pollutants. (C) 2001 John Wiley & Sons, Inc.