Photoacoustic analysis of the evolution from sols to aged gels: Comparison of different initial titania sols

The use of correlation analysis of photoacoustic signal changes during the sol-gel-aging evolution of titania sols prepared from the hydrolysis of titanium n-butoxide in alcoholic, aqueous, and micellar media which provide different initial conditions and different evolution pathways is proposed. Th...

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Autores principales: Marchi, María Claudia, Aldabe Bilmes, Sara Alfonsina Dora
Publicado: 2004
Materias:
Correlation analysis
Oscillating reactions
Phase transition
Photoacoustic
Sol-gel
TiO 2
Ceramic materials
Crystallization
Gelation
Heat treatment
Hydrolysis
Phase transitions
Photoacoustic effect
Sintering
Thermoanalysis
Thermogravimetric analysis
Distinguishable transition
Gelation time
Particle solvent interactions
Sol-gels
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0195928X_v25_n2_p491_Marchi
http://hdl.handle.net/20.500.12110/paper_0195928X_v25_n2_p491_Marchi
Aporte de:
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
id paper:paper_0195928X_v25_n2_p491_Marchi
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spelling paper:paper_0195928X_v25_n2_p491_Marchi2023-06-08T15:20:25Z Photoacoustic analysis of the evolution from sols to aged gels: Comparison of different initial titania sols Marchi, María Claudia Aldabe Bilmes, Sara Alfonsina Dora Correlation analysis Oscillating reactions Phase transition Photoacoustic Sol-gel TiO 2 Ceramic materials Crystallization Gelation Heat treatment Hydrolysis Phase transitions Photoacoustic effect Sintering Thermoanalysis Thermogravimetric analysis Distinguishable transition Gelation time Oscillating reactions Particle solvent interactions Sol-gels The use of correlation analysis of photoacoustic signal changes during the sol-gel-aging evolution of titania sols prepared from the hydrolysis of titanium n-butoxide in alcoholic, aqueous, and micellar media which provide different initial conditions and different evolution pathways is proposed. The photoacoustic experiments were done either at constant temperature for monitoring the initial evolution of the system, or under heating at 2°C·min -1 for monitoring molecular processes related to drying, sintering, and crystallization. Results obtained from photoacoustic measurements display higher sensibility when compared with those from differential thermal analysis (DTA) and thermogravimetric analysis (TGA). The evolution of these systems shows instabilities below and above gelation, as well as during thermal treatment. These stabilities are minimized when the thermal treatment is performed on gels aged several months, and can be associated to molecular rearrangements or oscillating chemical reactions. For all the systems studied, the sensitivity of the correlation analysis recovered from photoacoustic signals permits detection of a transition in the 100 to 150°C range. Fil:Marchi, M.C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Bilmes, S.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2004 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0195928X_v25_n2_p491_Marchi http://hdl.handle.net/20.500.12110/paper_0195928X_v25_n2_p491_Marchi
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Correlation analysis
Oscillating reactions
Phase transition
Photoacoustic
Sol-gel
TiO 2
Ceramic materials
Crystallization
Gelation
Heat treatment
Hydrolysis
Phase transitions
Photoacoustic effect
Sintering
Thermoanalysis
Thermogravimetric analysis
Distinguishable transition
Gelation time
Oscillating reactions
Particle solvent interactions
Sol-gels
spellingShingle Correlation analysis
Oscillating reactions
Phase transition
Photoacoustic
Sol-gel
TiO 2
Ceramic materials
Crystallization
Gelation
Heat treatment
Hydrolysis
Phase transitions
Photoacoustic effect
Sintering
Thermoanalysis
Thermogravimetric analysis
Distinguishable transition
Gelation time
Oscillating reactions
Particle solvent interactions
Sol-gels
Marchi, María Claudia
Aldabe Bilmes, Sara Alfonsina Dora
Photoacoustic analysis of the evolution from sols to aged gels: Comparison of different initial titania sols
topic_facet Correlation analysis
Oscillating reactions
Phase transition
Photoacoustic
Sol-gel
TiO 2
Ceramic materials
Crystallization
Gelation
Heat treatment
Hydrolysis
Phase transitions
Photoacoustic effect
Sintering
Thermoanalysis
Thermogravimetric analysis
Distinguishable transition
Gelation time
Oscillating reactions
Particle solvent interactions
Sol-gels
description The use of correlation analysis of photoacoustic signal changes during the sol-gel-aging evolution of titania sols prepared from the hydrolysis of titanium n-butoxide in alcoholic, aqueous, and micellar media which provide different initial conditions and different evolution pathways is proposed. The photoacoustic experiments were done either at constant temperature for monitoring the initial evolution of the system, or under heating at 2°C·min -1 for monitoring molecular processes related to drying, sintering, and crystallization. Results obtained from photoacoustic measurements display higher sensibility when compared with those from differential thermal analysis (DTA) and thermogravimetric analysis (TGA). The evolution of these systems shows instabilities below and above gelation, as well as during thermal treatment. These stabilities are minimized when the thermal treatment is performed on gels aged several months, and can be associated to molecular rearrangements or oscillating chemical reactions. For all the systems studied, the sensitivity of the correlation analysis recovered from photoacoustic signals permits detection of a transition in the 100 to 150°C range.
author Marchi, María Claudia
Aldabe Bilmes, Sara Alfonsina Dora
author_facet Marchi, María Claudia
Aldabe Bilmes, Sara Alfonsina Dora
author_sort Marchi, María Claudia
title Photoacoustic analysis of the evolution from sols to aged gels: Comparison of different initial titania sols
title_short Photoacoustic analysis of the evolution from sols to aged gels: Comparison of different initial titania sols
title_full Photoacoustic analysis of the evolution from sols to aged gels: Comparison of different initial titania sols
title_fullStr Photoacoustic analysis of the evolution from sols to aged gels: Comparison of different initial titania sols
title_full_unstemmed Photoacoustic analysis of the evolution from sols to aged gels: Comparison of different initial titania sols
title_sort photoacoustic analysis of the evolution from sols to aged gels: comparison of different initial titania sols
publishDate 2004
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0195928X_v25_n2_p491_Marchi
http://hdl.handle.net/20.500.12110/paper_0195928X_v25_n2_p491_Marchi
work_keys_str_mv AT marchimariaclaudia photoacousticanalysisoftheevolutionfromsolstoagedgelscomparisonofdifferentinitialtitaniasols
AT aldabebilmessaraalfonsinadora photoacousticanalysisoftheevolutionfromsolstoagedgelscomparisonofdifferentinitialtitaniasols
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