Página 1 dos resultados de 250 itens digitais encontrados em 0.001 segundos
Resultados filtrados por Publicador: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Química (IQ); Instituto de Química - IQ (RG)

Síntese e caracterização de compósitos polianilina/poli(estireno-co-divinilbenzeno) para Adsorção de Ânions [SnCl4]²-; Synthesis and characterization of composite polyaniline/poly(styrene-co-divinylbenzene)-resin for adsorption of anions [SnCl4]²-

Lima, Wolney Arruda de
Fonte: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Química (IQ); Instituto de Química - IQ (RG) Publicador: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Química (IQ); Instituto de Química - IQ (RG)
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
37.63332%
In this work were prepared and characterized polyaniline/poly(styrene-co-divinylbenzene) composites by in situ oxidative polymerization of aniline in the pores of styrene-divinylbenzene copolymers. The aim was to obtain composites with high specific surface areas and total pore volumes for use as adsorbents of complex anions [SnCl4]2-. The copolymers with 29 and 84 % of divinylbenzene (DVB) were called PStyDVB 29 and PStyDVB 84, respectively. They were synthesized by suspension polymerization in the presence of inert diluents like toluene and heptane to obtain mesoporous beads with sizes in the range of 400 to 800 μm. Before the oxidative polymerization, the copolymers were swelled with aniline and ethanol mixture at volumetric ratio 20:80. The oxidative polymerization of aniline in the copolymers was carried out using benzoyl peroxide as an oxidant in the presence of hydrochloric or nitric acid as dopant at 25°C in three polymerization cycles. The materials were characterized by infrared spectroscopy with Fourier transform (FTIR), elemental analysis (CNHS), X ray diffraction, thermogravimetry, nitrogen adsorption (specific surface area and pore volume), Scanning Electron Microscopy and Atomic Absorption spectrophotometry. Elemental analysis indicated that the composite doped with HCl adsorb higher amounts of polyaniline (PANI) than using HNO3. The FTIR spectra and X-ray diffraction patterns of the composites were similar to the ones of the copolymers due the low amounts of PANI incorporated. The copolymers had lower thermal stability than composites...