In this article we present the synthesis of poly(N-vinyl-2-pyrrolidinone) (PNVP)-vermiculite hybrid material and its characterization by various spectroscopic techniques, X-ray diffraction (XRD), and thermal analysis. The polymer was synthesized by intercalative redox polymerization of the monomer at 110 degrees C, using copper (II) ion-exchanged vermiculite. XRD analysis following intercalative polymerization indicates the presence of two prominent peaks with corresponding d (002) spacing of 14.3 (intercalated) and 9.9 (not intercalated) Angstrom, suggesting the formation of a partially intercalated hybrid material. Electron spin resonance studies of the intercalated material show values of "g" different from that of the Cu (II)-ion-exchanged vermiculite, indicating that polymer formed in the gallery of vermiculite complexes with the unreacted Cu (II). Thermogravimetric analysis indicates the amount of polymer in the gallery spacing to be approximate to 20 mass %, which is confirmed by I-2 labeling of the PNVP in the nanocomposite, followed by UV spectroscopy. The IR absorption peaks corresponding to PNVP, along with the XRD and thermal analysis data confirms that the gallery expansion is due to the formation of a partially intercalated inorganic-organic hybrid material. (C) 2000 John Wiley & Sons, Inc.