Effects of some solvents on the thermal and free-volume properties of poly(4-vinylpyridine) complexes

摘要

Modified poly(4-vinylpyridine) (P4VP) and its complexes were prepared with different solvents such as benzene, toluene, and xylene as well as potassium chloride (KCl) and copper chloride (CuCl2). Fourier transform infrared spectroscopy, thermal analysis, and positron annihilation spectroscopy were Used to investigate the properties of the modified P4VP and its complexes. It was concluded that complexes were formed between the polymer and solvents via quaternization of nitrogen in the ring with the solvents and also with KCl and CuCl2 center dot 2H(2)O. Furthermore, the modified P4VP-CuCl2 complexes were more stable than the modified P4VP-KCl complexes, and these complexes were more stable than the MP-solvent complexes. Ortho-positronium components (tau(3), I-3) were used to estimate the nanoscale free-volume hole size (V-f) and the free-volume fraction (f %). The free-volume hole size and its fractions depended on the addition of solvents and metals to the polymer. (C) 2008 Wiley Periodicals, Inc.