The present invention is directed, in part, to improved nanocomposite compositions
and processes for preparing same. In one embodiment, there is provided a process
for preparing an aqueous nanocomposite dispersion, wherein the process comprises:
providing at least one first ethylenically unsaturated monomer; providing an aqueous
clay dispersion comprising an at least partially exfoliated aqueous clay having
a first exchangeable cation and, optionally, at least one second ethylenically
unsaturated monomer; adding a second cation to said aqueous clay dispersion, wherein
at least a portion of the second cation exchanges with at least a portion of the
first cation to form a modified aqueous clay dispersion; combining the first ethylenically
unsaturated monomer and the modified aqueous clay dispersion; and polymerizing
at least a portion of the first or second monomer to form the aqueous nanocomposite
dispersion wherein at least one of the first or the second monomers comprises a
polar monomer.
