How can I delaminate and disperse (exfoliate) Cloisite® nanoclays?
A. Thermosets: It is assumed the Cloisite® will be added to a liquid component of the thermoset. Below are some general guidelines for dispersing an organoclay in a liquid. Other processing techniques can be used. High shear mixing is required. As an example, mixing can be done using a Cowles Dissolver, a round blade with teeth at about 1/3 the tank diameter, turning at high rpm with a tip speed of ~65 feet per second. For a five inch blade this is 1000-3000 rpm. There should be baffles in the tank. We try to ensure a good vortex is accomplished. There are literature reports that for epoxy resins increasing the temperature aids in exfoliation. Temperature of 110°C>90°C >60°C. There is also literature recommending cryogenic mixing. Compatibility of the liquid with the organoclay is critical. Dispersion of the product could be accomplished at low shear rates if the compatibility is good and enough time is allowed. More time allows more energy, and eventually the clay could disperse. If n
