The present invention relates to a composition comprising (i) a layered clay material that has been cation-exchanged with an organic cation salt represented by Formula (I): ##STR1## wherein M is nitrogen or phosphorous, X.sup.- is a halide, hydroxide, or acetate anion, R.sub.1 is a straight or branched alkyl group having at least 8 carbon atoms, and R.sub.2, R.sub.3, and R.sub.4 are independently hydrogen or a straight or branched alkyl group having 1 to 22 carbon atoms; and (ii) at least one expanding agent, wherein the cation-exchanged clay material contains platelet particles and the expanding agent separates the platelet particles. The present invention also relates to a composite comprising a polymer having dispersed therein a composition of this invention. Preferred polymers for use in the composite include polyesters. The composite of the present invention shows vastly improved platelet separation as evidenced by higher than previously reported basal spacing.