Characterization of Chitin-Based Polymer Hybrids by Temperature-Programmed Analytical Pyrolysis Techniques. 2. Chitin- g raft -poly(2-methyl-2-oxazoline)/Poly(vinyl alcohol) Blends

Chitin- graft -poly(2-methyl-2-oxazoline)/poly(vinyl alcohol) (PVA) blends were characterized by means of analytical pyrolysis techniques such as temperature-programmed pyrolysis−mass spectrometry (TPPy−MS), TPPy−gas chromatography (TPPy−GC) and Py−GC mainly in terms of their miscibility and the site of the intermolecular interaction. The thermal degradation of the chitin derivative/PVA blends took place apparently in two stages reflecting the degradation of both constituent polymers. However, peak-top temperatures for both degradation stages changed as a function of blend composition; the first degradation stage, mostly corresponding to the dehydration of PVA, shifted to higher temperatures when the chitin derivative content is increased in the blend. Although the yields of 2-butenal from the PVA moiety increased by blending the chitin derivative, those of acetamide and N -ethylacetamide from the chitin derivative moiety exhibit an opposite trend. These temperature shifts and the variations in the yields of the pyrolysis products suggested that intermolecular interactions might be contributing to a differing extent as a function of the blend composition. Moreover, the observed degradation behaviors for the chitin derivative/PVA blends showed the opposite trend for the case of the chitin derivative/PVC blend system previously investigated. Thus, the observed degradation mechanisms of this blend system were discussed by comparison with those for the chitin derivative/PVC blend system.