Thermal properties, interactions, morphologies, and conductivity behavior in blends of poly(vinylpyridine)s and zinc perchlorate

Abstract

We have investigated the physical properties and specific interaction of two regioisomeric poly(vinylpyridine)s-poly(2-vinylpyridine) (P2VP) and poly(4-vinylpyridine) (P4VP)-blended with zinc perchlorate. Analyses by differential scanning calorimetry indicate that the values of T-g of the poly(vinylpyridine)s increase significantly upon blending with zinc perchlorate. The values of Tg of P2VP and P4VP increase by 119 and 154 degreesC, respectively, relative to their corresponding pure polymers, upon blending with 40 and 30 wt %, respectively, zinc perchlorate. On the basis of the extended configuration entropy model equation, the interaction strength of the zinc salt/P4VP blend (3.60) is greater than that of the zinc salt/P2VP blend (3.55). The interaction between the polymer and the zinc ion was confirmed by infrared, X-ray photoelectron, and solid-state NMR spectroscopies, which suggest that the zinc cation coordinates to pyridine units in a metal-ligand bonding mode. In addition, the strength of the interaction between the polymer and the zinc ion is influenced by the different steric demands of the two polymer structures. A good correlation is found in the morphology of these polymer/zinc salt blends as determined by wide-angle X-ray diffraction and solid-state NMR T-1rho(H) measurements.