Blends of polystyrene/poly (4-vinylpyridine) have been prepared by casting from a common solvent. The compatibility of the blends was studied by using dilute solution viscometry (DSV), differential scanning calorimetery (DSC), Fourier transformation-infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). The relative viscosity versus composition plots for the blends are not perfect linear. The corresponding intrinsic viscosity values show negative deviation from ideal behavior when plotted against composition. Also, the modified Krigbaum and Wall interaction parameter, Db, shows small and negative values for all compositions except for the blend PS/P4VP (25 : 75). The results indicate that the polymers are incompatible but small interaction values predict physically miscible blends which eventually show phase separation, as is observed in the present studies. However, the blends as obtained show a single, composition-dependent, glass transition temperature that fits the Fox equation well, indicating the presence of homogeneous phase. The constant, k obtained from Gordon-Taylor equation suggests intermolecular attraction between these polymers. FT-IR and SEM support the results of DSV and DSC.

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Plaques of blends of Eudragit RL 100 (EU) and poly(methyl methacrylate) (PMMA) with different weight-per-weight ratios were prepared by compression molding at 150°C. The X-ray diffraction profiles of the blends were studied and compared, and the interplanar distance, crystallite size, and crystallinity were computed for various peaks. The Eu/PMMA blend with a 70:30 (w/w) ratio had the maximum crystallinity.

Dispersing silver nanoparticles homogeneously into a polymer matrix byex situmethods is difficult because of the easy agglomeration of nanoparticles. Therefore, convenient and effective ways of preparing Ag nanoparticles in polymer materials are still in strong demand. Vacuum deposited thin discontinuous silver films on the composite of Poly (vinylpyrrolidone) (PVP) and poly (4-vinylpyridine) (P4VP) is an in situ and eco friendly method. Films on softened PVP give rise to a very high room temperature resistance approaching that of the substrate resistance indicating non uniform formation of silver clusters. On the other hand, films on softened P4VP gives rise to a room temperature resistance in the range of a few tens to a few hundred MW/€, which is desirable for device applications due adequate size and uniform dispersal of silver clusters in P4VP. Silver films on PVP/P4VP blend show room temperature resistances in the desirable range indicating uniform subsurface formation of silver films on PVP/P4VP. The Electrical, optical and plasmonic response of Ag NP onto thin layers of PVP/P4VP shows encapsulation of nanoparticles. Silver nanocomposite film exhibits characteristic UV absorbance spectrum at a wavelength of 430 nm, due to the surface plasmon resonance of nanosized silver. Silver ions being bioactive killed bacteria on infected wounds on living tissue and led physician to use wound dressing containing silver sulfadiazine and Ag NP to treat external infections. Silver lining food helps in treating various remedies and ailments.

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