Abstract
Boehmite sols were obtained by peptizing boehmite precipitates with glacial acetic acid. The sols were aged at room temperature (30 ±1°C) under closed condition. Rheological properties of the sols were studied at different ageing times. The sol characteristics were interpreted by measuring their viscosity, areas of hysteresis of the flow curves and yield stress (τy). Viscosity and the area of hysteresis of the flow curves increased with increasing ageing time of the sols. A sharp change of yield stress was observed during the ageing period from 15 to 36 days. The change in viscous to elastic nature and the appearance of gel point of the sol was observed by studying their oscillatory flow behaviour, i.e. by measuring loss modulus(G″), elastic modulus (G′), and loss tangent (tan δ) of the sols. Gel point of boehmite sol was found at 36 days of ageing under closed condition at room temperature (30 ±1°C).
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References
Casson N 1959 inRheology of disperse system (London: Pergamon)
Chatterjee M, Enkhtuvshin D, Siladitya B and Ganguli D 1998J. Mater. Sci. 33 4937
Drouin J M, Chopin T, Nortier P and Van Damme H 1988J. Colloid Interface Sci. 125 314
Ganguli D and Chatterjee M 1997 inCeramic powder preparation: A handbook (USA: Kluwer Academic Publishers) p. 111
Gonzalez C, Gutierrez J, Galan M I and Mans C 1992J. Non-Cryst. Solids 147 & 148 690
Guo L-C, Zhang Y, Uchida N and Uematsu K 1998J. Am. Ceram. Soc. 81 549
Kiratzis N and Luckham P E 1998J. Eur. Ceram. Soc. 8 783
Kozuka H, Kuroki H and Sakka S 1987J. Non-Cryst. Solids 95 1181
Kozuka H, Kuroki H and Sakka S1988J. Non-Cryst. Solids 101 120
Kwon T M, Jhon M S and Choi H 1997J. Mater. Chem. Phys. 49 225
Sacks M D and Sheu R-S 1987J. Non-Cryst. Solids 92 383
Sakka S and Kozuka H 1988J. Non-Cryst. Solids 100 142
Schramm V G 1995 inHaake rheometer: Introduction to rheometry (Karlsruhe, Germany: Gebruder Haake GmbH)
Song K C and Chung I J 1989J. Non-Cryst. Solids 107 193
US Patent 1986 No. 4623364
Yoldas B E 1975aAm. Ceram. Soc. Bull. 54 289
Yoldas B E 1975bJ. Mater. Sci. 10 1856
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Naskar, M.K., Chatterjee, M. & Ganguly, D. Rheological properties of boehmite sols during ageing at room temperature (30 ±1°C) under closed condition. Bull Mater Sci 25, 115–119 (2002). https://doi.org/10.1007/BF02706230
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DOI: https://doi.org/10.1007/BF02706230