Nylon-intercalated (concentrate nylon), layered silicates, in concentrated form, containing at least 6% to about 40% by weight layered silicate, preferably about 8% to about 30% by weight layered silicate, intercalated with a nylon that is polymerized while in contact with the clay, during ring-opening polymerization of the nylon reactants (monomers) and melt processing. The in-situ nylon polymerization reaction to form the concentrate nylon is continued until the number average molecular weight (Mn) of the nylon is about 25,000 or less, preferably 15,000 or less, more preferably about 5,000-10,000, to maintain melt processability of the resulting concentrate.