Films of polyvinyl alcohol (PVA), sodium carboxy methyl cellulose homopolymer and their blends of composition 0.7/0.3, 0.5/0.5, 0.3/0.7 (wt/wt) were prepared using cast technique. The influence of blend composition of PVA/NaCMC has been investigated by thermo-gravimetric analysis (TGA) and IR and UV/VIS spectra. From TGA and its derivative DTGA it was found that the thermal stability of the blend samples is increased with increasing NaCMC content. The kinetic parameters such as activation energy, entropy, enthalpy and free energy in the first and second decomposition steps based on thermo gravimetric data were determined. The IR studies indicated that PVA/NaCMC are miscible in the full composition range. The apparent degree of crystallinity of each polymer is decreased with increasing content of the blending partner in most samples. The analysis of the UV/VIS spectra provided an evidence for miscibility conformed by the absorption edge and the band tail. Sample 0.5/0.5 (wt/wt) PVA/ NaCMC is the most optimum miscible blend one.
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