Artículos de revistas
Anisotropic self-organization of hybrid silica based xerogels containing bridge positively charged 1,4-diazoniabicycle[2.2.2]octane chloride group
Registro en:
Journal Of Colloid And Interface Science. Academic Press Inc Elsevier Science, v. 318, n. 1, n. 96, n. 102, 2008.
0021-9797
WOS:000251559300013
10.1016/j.jcis.2007.09.073
Autor
Arenas, LT
Pinheiro, AC
Ferreira, JD
Livotto, PR
Pereira, VP
Gallas, MR
Gushikem, Y
Costa, TMH
Benvenutti, EV
Institución
Resumen
Anisotropic self-organized hybrid silica based xerogels were obtained. The ordered structure was imposed by the double charged 1,4-diazoniabicycle[2.2.2]octane chloride group bonded in a bridged way. This was confirmed by the presence of well defined X-ray diffraction peaks corresponding to an interplanar distance with the same length estimated for the organic bridged groups. The material was characterized by elemental analysis using CHN technique and the chloride ion was analyzed by a potentiometric titration. C-13 and Si-29 CP MAS solid state NMR spectroscopy and thermogravimetric analysis were also performed. The material that can be obtained in the form of powders and transparent monoliths or films, is thermally stable up to 260 degrees C and the samples with high organic content presented birefringence properties. (c) 2007 Elsevier Inc. All rights reserved. 318 1 96 102