Effect of nickel chloride concentration and gamma radiation on the thermal properties of poly(vinyl alcohol)

The effect of addition of nickel chloride (NiCl2), with different concentrations, to poly(vinyl alcohol) (PVA), has been investigated. Non-isothermal studies were carried out using thermogravimetric analysis (TGA) to obtain the activation energy of decomposition for PVA doped with NiCl2. TGA indicated that the PVA–NiCl2 samples decompose in one main break-down stage. The results indicated that the addition of NiCl2 with concentrations above 8% and up to 20% enhances the thermal stability of pure PVA. In addition, samples from pure PVA were irradiated with gamma doses at levels between 20 and 100 kGy. TGA was performed on both irradiated and non-irradiated PVA samples. The thermal activation energies of decomposition were found to be dependent on the gamma dose. Moreover, the variation of transition temperatures with either the NiCl2 concentration or the gamma dose has been determined using differential thermal analysis. The results indicated that the PVA samples were characterized by the appearance of an ...