Thermal stability of some cryogels based on poly(vinyl alcohol) and cellulose

The aim of this study consisted in the elucidation of the thermal decomposition process of some cellulose and poly(vinyl alcohol) based cryogels as films. The thermal behavior was studied by dynamic thermogravimetry and differential scanning calorimetry in nitrogen atmosphere, up to 600 C. Evolved gases analysis were performed using a coupling to a quadrupole mass spectrometer and a Fourier transform infrared spectrophotometer equipped with external modulus for gas analyses. Global kinetic parameters of the thermal decomposition process were determined by applying the isoconversional differential method of Friedman and the integral method of Flynn-Wall-Ozawa. The final form of the kinetic model and the parameters for each individual stage of thermal decomposition were determined by multivariate non-linear regression method. (C) 2013 Elsevier B.V. All rights reserved.