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The invetion is directed to a polymer-clay nanocomposite material comprising a melt-processible matrix oplymer and a layered clay material having decreased levels of extractable material, such as extractible salts of organic cations. This invention is also derected to processes for preparing polymer

The invetion is directed to a polymer-clay nanocomposite material comprising a melt-processible matrix oplymer and a layered clay material having decreased levels of extractable material, such as extractible salts of organic cations. This invention is also derected to processes for preparing polymer-clay nanocomposites, intercalates, exfoliates, and articles or products produced from nanocomposite materials.

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1. A process for preparing a cation-exchanged intercalate having a decreased level of extractable cations without washing excess cations from the intercalate after ion-exchange comprising the step of:containing a layered clay material with an organic cation after analysis of the clay material to det

1. A process for preparing a cation-exchanged intercalate having a decreased level of extractable cations without washing excess cations from the intercalate after ion-exchange comprising the step of:containing a layered clay material with an organic cation after analysis of the clay material to determine an amount of said organic cation within the range of 0.95 and 1.05 moles of organic cation for each mole of exchangeable cations in the layered clay material, wherein the moles of exchangeable cations in the layered clay is determined empirically in order to approximate an equimolar quanity of organic cation to intercalate into the clay by titrating the clay with an organic cationic indicator that cation-exchanges with the exchangeable cations in the clay and provides an indication when all exchangeable cations have been ion-exchanged with cations from the indicator. 2. The process of claim 1, further including the step of intercalating the cation-exchanged layered clay material with an oligomer or polymer intercalant. 3. The process of claim 1, wherein the oligomer or polymer intercalant is intercalated into the layered clay material in a batch mixing or a melt compounding extrusion process. 4. The process of claim 1 further including the step of shearing the intercalate in a suitable carrier to delaminate the intercalate such that at least 50 percent of the layered clay material is dispersed in the form of individual platelet particles and tactoids and the individual platelet particles have a thickness of less than 2 nm and a diameter of from about 10 to about 3000 nm. 5. The process of claim 1, further including the step of extracting any excess cations from the organic cation-contacted layered material to determine by trial and error if an amount of organic cations intercalated into the layered clay material should be raised or lowered from the approximate cation amount determined by titration. 6. The process of claim 1, further including the steps of incrementally raising or lowering the amount of organic cations intercalated into the layered clay material and analyzing the layered clay material for excess cations until the amount of cations added to the layered clay material for intercalation is in the range of 0.95 to 1.05 moles of organic cation for each mole of exchangeable cations in the layered clay material. 7. The product made by the process of claim 2. 8. The product made by the process of claim 3. 9. The product made by the process of claim 4. 10. The product made by the process of claim 5. 11. The product made by the process of claim 6. 12. A cation-exchanged intercalate that is prepared by the process of claim 1. 13. The intercalate of claim 12, wherein the organic cation is an onium salt. 14. The intercalate of claim 12, wherein the organic cation has the formulawherein M is either nitrogen or phosphorous, and R 1 , R 2 , R 3 , and R 4 are independently organic and/or oligomeric ligands or may be hydrogen. 15. The intercalate of claim 14, wherein the organic cation is an ammonium salt. 16. The intercalate of claim 12, wherein the cation-exchanged layered clay material is intercalated with an intercalant oligomer or polymer selected from the group consisting of a polyester, polyetherester, polyamide, polyesteramide, polyuerthane, polyimide, polyetherimide, polyurea, polyamideimide, polyphenyleneoxide, phenoxy resin, epoxy resin, polyolefin, polyacrylate, polystyrene, polyethylene-co-vinyl alcohol, a copolymer thereof, and a mixture thereof. 17. The intercalate of claim 16, wherein polymer intercalant comprises a partially aromatic polymide, aliphatic polyamide, wholly aromatic polyamide or a mixture thereof. 18. The intercalate of claim 16, wherein the polymer intercalant comprises poly(m-xylylene adipamide) or a copolymer thereof, isophthalic acid-modified poy(m-xylylene adipamide), nylon-6, nylon-6,6 or a copolymer thereof, EVOH or a mixture thereof. 19. The intercalate of claim 12, wherein the layered clay material comprises montmorillonite, hectorite, mica, vermiculite, bentonite, nontronite, beidellite, volkonskoite, saponite, magadite, kenyaite, or a mixture thereof. 20. The intercalate of claim 12, wherein the layered clay material comprises sodium montmorillonite sodium bentonite. 21. An exfoliate made by delaminating the intercalate of claim 12 such that at least 50 percent of the layered clay material is dispersed in the form of individual platelet particles and tactoids in a carrier and the individual platelet particles have a thickness of less than 2 nm and a diameter of from about 10 to about 3000 nm.