Patent ID: 8357743

Claim:
A method for dispersing exfoliated fibrous clay nanoparticles in a polyester that is produced from a reaction mixture containing one or more diols and one or more dicarboxylic acids or esters of dicarboxylic acids, comprising: (a) providing a mixture of exfoliated fibrous clay nanoparticles, at least one diol, at least one sodium salt, and water; (b) agitating the mixture for a time sufficient to fully disperse the exfoliated fibrous clay nanoparticles in the mixture; (c) removing at least 80% of the water, thereby producing a slurry of exfoliated fibrous clay nanoparticles dispersed in the at least one diol and the remaining water; (d) preparing a reaction mixture by mixing the slurry produced in (c) with one or more dicarboxylic acids or esters of dicarboxylic acids and at least one diol as needed for polymerization; and (e) polymerizing the reaction mixture prepared in (d) in the presence of a catalyst, wherein the amount of water in step (a) is about 46 wt % to about 57% wt % based on the weight of water and diol.