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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.

Structural effects of chain extender on phase mixing and coating properties of polyether-based moisture-cured polyurethane ureas (MCPUs) were determined with a polytetramethylene glycol (PTMG-1000), trimethylol propane (TMP), and isophorone diisocyanate (IPDI)-based system. The reaction of PTMG/TMP/IPDI was carried out using a NCO/OH ratio of 1.6:1. The excess isocyanate of the prepolymer was chain extended in the ratio of 2:1 (NCO/OH) with different aliphatic diols and 4:1 with different aromatic diamines just before the coating application. The viscoelastic properties of the cross-linked films were evaluated with a dynamic mechanical and thermal analyzer (DMTA). The mechanical film properties such as tensile strength, adhesion strength, and hardness were measured and related to chemical composition and cohesion of the hard segment. Surface properties were evaluated through angle resolved X-ray photoelectron spectroscopy (AR-XPS). The degree of phase mixing was found to be dependent on the chain extender structure. The results indicate that the combined analysis of the hard segment cohesion helps in correlating the structure-to-property relationship.