Structural properties of CrF3- and MnCl2-filled poly(vinylalcohol) films

Poly(vinylalcohol) (PVA) films filled with different filling levels of CrF3 and MnCl2 have been prepared by the casting method. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis were used to study the changes in structure properties that occur due to filling. The changes occurring in the measured parameters with increasing the filler content was been interpreted in terms of the structural modification of the PVA matrix. It was found that all studied samples had the main melting temperature due to the main crystalline phase of PVA. The intensity and position of this peak depended on the filling level. On the other hand, the samples of CrF3-filled PVA films with filling level W greater than or equal to 10 wt % revealed another melting temperature, indicating the presence of a new crystalline phase besides the main crystalline phase. Changes occurring in the degree of crystallinity of the studied samples were discussed. The calculated degree of crystallinity was formulated numerically to be an exponential function of filling level. The X-ray diffraction patterns of the studied samples confirmed the DSC results. (C) 2003 Wiley Periodicals, Inc.