caa a22 4500 463191749 CHVBK 20180406164911.0 cr unu---uuuuu 170326e20070801xx s 000 0 eng 10.1007/s10973-006-7623-1 doi (NATIONALLICENCE)springer-10.1007/s10973-006-7623-1 Pyrolysis study of a hydride-sol-gel silica [Elektronische Daten] Part I. Chemical aspects [R. Campostrini, A. Sicurelli, M. Ischia, G. Carturan] A homogeneous silica gel sample bearing ≡Si-H groups was prepared, via sol-gel method, by hydrolysis of trimethoxysilane under acid condition in tetrahydrofuran. Preliminary NMR experiments in liquid phase indicated an immediate and complete hydrolysis of Si-OCH3, followed by a slower condensation of the Si-OH groups, with maintenance of Si-H bonds. The crude-gel, and samples heated to various temperatures, were characterized by different instrumental methods, including FTIR, density, porosity, and specific surface area. These data indicate that the crude-gel was a dense material which, on heating, increases porosity and surface area up to ca 500°C. The thermal behavior was studied in inert atmosphere by means of coupled thermogravimetric, gas chromatographic, mass spectrometric analyses. The pyrolysis process was described by the fundamental chemical reactions occurring among the siloxane chains of the gel network and by the qualitative and semiquantitative chemical analysis of the compounds released in gas-phase. The proposed pyrolysis mechanism was discussed and interpreted in agreement with the change of the morphological properties of the gel. The pyrolysis data and the mass balance between the compounds released in gas-phase and the solid residue at 1000°C allowed the determination of a nominal chemical formula to describe the crude-gel composition. Springer Science+Business Media LLC, 2007 hydride silica gel nationallicence pyrolysis study nationallicence sol-gel synthesis nationallicence thermogravimetric-mass spectrometric gas chromatographic coupled analyses nationallicence Campostrini R. Dipartimento di Ingegneria dei Materiali e Tecnologie Industriali, Universitŕ di Trento, via Mesiano 77, 38050, Trento, Italy aut Sicurelli A. Dipartimento di Ingegneria dei Materiali e Tecnologie Industriali, Universitŕ di Trento, via Mesiano 77, 38050, Trento, Italy aut Ischia M. Dipartimento di Ingegneria dei Materiali e Tecnologie Industriali, Universitŕ di Trento, via Mesiano 77, 38050, Trento, Italy aut Carturan G. Dipartimento di Ingegneria dei Materiali e Tecnologie Industriali, Universitŕ di Trento, via Mesiano 77, 38050, Trento, Italy aut Journal of Thermal Analysis and Calorimetry Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 89/2(2007-08-01), 633-641 1388-6150 89:2<633 2007 89 10973 https://doi.org/10.1007/s10973-006-7623-1 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10973-006-7623-1 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Campostrini R. Dipartimento di Ingegneria dei Materiali e Tecnologie Industriali, Universitŕ di Trento, via Mesiano 77, 38050, Trento, Italy aut NATIONALLICENCE 700 1- Sicurelli A. Dipartimento di Ingegneria dei Materiali e Tecnologie Industriali, Universitŕ di Trento, via Mesiano 77, 38050, Trento, Italy aut NATIONALLICENCE 700 1- Ischia M. Dipartimento di Ingegneria dei Materiali e Tecnologie Industriali, Universitŕ di Trento, via Mesiano 77, 38050, Trento, Italy aut NATIONALLICENCE 700 1- Carturan G. Dipartimento di Ingegneria dei Materiali e Tecnologie Industriali, Universitŕ di Trento, via Mesiano 77, 38050, Trento, Italy aut NATIONALLICENCE 773 0- Journal of Thermal Analysis and Calorimetry Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 89/2(2007-08-01), 633-641 1388-6150 89:2<633 2007 89 10973 Metadata rights reserved Springer special CC-BY-NC licence nationallicence SWISSBIB 463189590 BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer