Water soluble nanocomposite films based on poly(vinyl alcohol) and chemically modified montmorillonites

Different montmorillonites were added to poly(vinyl alcohol) in order to improve their properties. The used montmorillonite's were: Cloisite Na+ (Na), Nanofil (NF), and Cloisite 30B (30B). Poly(vinyl alcohol) + montmorillonite films, obtained by casting, were characterized by means of Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, X-ray diffraction pattern, transmission electron microscopy, water absorption, contact angle, and mechanical properties. Sodium and organically modified montmorillonites were used. The montmorillonite basal peak shifted to a lower angle for composites, with sodium montmorillonites, and the films were exfoliated-intercalated nanocomposites. Composites with organically modified montmorillonites presented a micro-morphology and the lowest water absorption. The best mechanical properties were obtained for the composite with sodium montmorillonites.