The Processing and Characterization of DCCA Modified Gel-Derived Silica

Conclusions

Formamide is the first DCCA that shows the feasibility of the use of organic solvents as a means of improving the processing of metal organic derived gels. It reduces gelation, aging, drying times, the drying stress, and increases the size of gel monolith that can be made up to about 100 cm3 after drying for 2 days. This is facilitated by acid catalysis and the correct solvent volume. The acid catalysis caused rapid hydrolysis allowing a stronger gel to be formed. FTIR spectroscopy liquid cell monitoring of the sol reactions confirms the influence of HNO3 and NH2CHO on the sol reaction rates. A DCCA modified silica gel can be densified by 1000°C without devitrification, but further work on a new DCCA is needed to densify large monoliths.

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Correspondence to S. Wallace.

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Wallace, S., Hench, L.L. The Processing and Characterization of DCCA Modified Gel-Derived Silica. MRS Online Proceedings Library 32, 47 (1984). https://doi.org/10.1557/PROC-32-47

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