1. Insights into PhotoinducedSol–Gel Polymerization:An in SituInfrared Spectroscopy Study.
- Author
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De Paz, Héloïse, Chemtob, Abraham, Croutxé-Barghorn, Céline, Le Nouen, Didier, and Rigolet, Séverinne
- Subjects
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PHOTOPOLYMERIZATION , *HYDROLYSIS , *SOL-gel processes , *INFRARED spectroscopy , *PHOTOCATALYSIS , *FOURIER transform infrared spectroscopy - Abstract
Photoacid-catalyzed sol–gel polymerization isnow recognizedas a powerful single-step synthetic approach to the synthesis of hybridfilms, which can be distinguished from conventional sol–gelmethods by higher reactivity and a solvent-free process. Despite itsutility, the mechanism is not yet understood, in particular what chemical,physical, and photochemical parameters determine the precise sequence,kinetics, and advancement of this UV inorganic photopolymerization.Here, using mainly transmission real-time Fourier transformed infrared(RT-FTIR) spectroscopy, we characterize in situthehydrolysis–condensation reactions of oligomeric silicon alkoxidesand the formation of byproducts. Systematic review and assessmentof numerous processing variables (relative humidity, film thickness,precursor structure, nature, and the concentration of photoacid generator)prove that the reaction kinetics are controlled by the two independentphenomena: the intrinsic chemical reaction rates and the water vaporpermeation into the film. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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