Starch-poly(vinyl alcohol) (PVA) blends with different compositions were prepared and crosslinked with borax by in situ and posttreatment methods. Various amounts of glycerol and poly(ethylene glycol) with a molecular weight of 400 were added to the formulations as plasticizers. The pure starch-PVA blends and the crosslinked blends were subjected to differential scanning calorimetry, thermogravimetry, and X-ray photoelectron spectroscopic studies. Broido and Coats-Redfern equations were used to calculate the thermal decomposition kinetic parameters. The tensile strengths and elongation percentages of the films were also evaluated. The results suggested that the glass-transition temperature (T g ) and the melting temperature strongly depended on the plasticizer concentration. The enthalpy relaxation phenomenon was dependent on the starch content in the pure blend. The crosslinked films showed higher stability and lower T g 's than pure PVA and starch-PVA blends, respectively. High-resolution X-ray photoelectron spectroscopy provided a method of differentiating the presence of various carbons associated with different environments in the films.

Conductive polyaniline salts were synthesized by inverted emulsion polymerization method and were characterized by thermogravimetric analysis (TGA), thermogravimetry-mass (TGA-MS) analysis, and X-ray photoelectron spectroscopy (XPS) methods. The various characteristic fragments evolved during the thermal degradation of polyaniline were identified. The weight loss of dopants as well as sodium lauryl sulfate decomposition were identified at different temperatures from TGA-MS analysis. The kinetic analysis of the thermal decomposition processes of polyaniline in doped state was performed. Broido, Chang, and Friedman methods were used for the evaluation of kinetic parameters in nitrogen atmosphere. High resolution XPS analysis was used to provide a method of differentiating the presence of nitrogen and carbon associated in the different environments in the polyaniline base and doped-samples.

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Biodegradable polymers are desirable for a variety of applications, such as in packaging, agriculture, and medicine. Polyethylene (PE) blended with starch is already found to be a potential candidate to replace nondegradable thermoplastics in the areas of packaging. Films of polyethylene (PE)-starch blends with and without vegetable oil as a compatibilizer were prepared. The degradation of the films under thermooxidative treatment, ultraviolet light exposure, high temperature, high humidity, and natural ambience (soil burial) were monitored. It is seen that vegetable oil as an additive has a dual role: as a plasticizer, it improves the film quality; as a prooxidant, it accelerates degradation of the film.

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