Hectorite, viscosity

Other mineral additives have been used for many years as functional extenders and fillers in adhesives and sealants. These include kaolin (hydrated aluminum silicate), bentonite (hectorite clay), talc (magnesium silicate), and attapulgite (hydrated magnesium aluminum silicate) additives.1213 Kaolin and talc are considered to be viscosity thickeners whereas attapulgite is more of a conventional thixotrope. They are considered to be very cost-effective rheological additives. 

FIGURE 12.23 Plot of low and high shear viscosity versus volume fraction for hectorite platelets with lit equations that follow for a = 33.175 nm, b/a = 45 2. 

Hectorite is used widely in pharmaceutical preparations as an absorbent, emulsifier, stabilizen suspending agent, thickener, and viscosity-controlling agent. ... 

Comments quaternium 18-hectorite is used in cosmetics as a viscosity-controlling agent. It does not contain crystalline silica. The EINECS numbers for quaternium 18-hectorite are 234-406-6, and 234-406-6. 

McBride, M.B., and P. Baveye. 1995. Mobility of anion spin probes in hectorite gels Viscosity of sur-ftcial water. Soil Sci. Soc. Am. J. 59 388-394. 

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