Interaction of functional groups of gelatin and montmorillonite in nanocomposite

As an amphoteric polyelectrolyte, gelatin could intercalate into the galleries of montmorillonite (MMT). In this paper, sodium laurate/MMT composites and sodium laurate/dehydroxylated MMT composites were introduced as low molecular simulation to investigate the interaction functional groups of gelatin and MMT. The composites were characterized by X‐ray diffraction (XRD), Fourier transform infrared spectra (FTIR), thermogravimetric analysis (TGA) and ¹³C nuclear magnetic resonance (¹³C NMR). Furthermore, the effect of interaction between gelatin and MMT on the mechanical properties of the composites was investigated. The results indicated that ? COO^?, not ? COOH, in gelatin chains could interact strongly with the MMT sheets. The reactive sites on MMT were hydroxyl groups, which could interact with ? COO^? in gelatin chains by forming hydrogen bonds. The gelatin/MMT composites prepared in alkalic media have better mechanical properties due to stronger interaction. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1556–1561, 2006