The IR spectroscopy study shows miscibility between PMMA-PVC blends due to hydrogen bonding between C¼O of PMMA and hydrogen from CHCl of PVC. This blend system is doped by Camphor Sulphonic Acid (CSA) in the entire composition range. The doping of CSA in PVC, in PMMA and in PMMA-PVC blends shows changes in FTIR spectra. The interaction between PVC and CSA is through hydrogen bonding between C¼O of CSA and CHCl of PVC. Doping PMMA with CSA, indicate an interaction between H þ ion of CSA and oxygen atoms of C¼O and -OCH 3 of PMMA. Whereas in PMMA-PVC blend interaction between H þ ion of CSA and oxygen atom of C¼O of PMMA.

PMMA, PVC and their five blends in different compositions were irradiated by γ -rays of 2 Mrad dose. A comparative study of structural, morphological and mechanical properties of irradiated and non-irradiated samples was carried out. The structural changes that have taken place due to irradiation are seen in the FTIR and X-ray diffraction (XRD) spectra. The ester group is mainly affected in PMMA and the blends. The XRD results have confirmed that the irradiated samples are more amorphous in nature than the non-irradiated ones. The DSC study reveals that some irradiated samples undergo cross-linking, whereas some of them undergo degradation. One of the irradiated blend compositions has become thermally more stable. The SEM study suggests that the irradiated samples have undergone curing. An improvement in the mechanical properties has been observed in some of the irradiated blend compositions.

The compounds with general chemical formula BaFe12-2xZnxTixO19 (x = 0.0, 1.0, 1.5, 2.0), were synthesized by ceramic method. X-ray diffraction (XRD) confirmed the formation of single phase magneplumbite structure. The EDS spectra confirmed the presence of all the constituents. The lattice parameter a decreased whereas c increased with the increase in x. Magnetic parameters like coercivity, saturation magnetization decreased with increase in substitution. Superparamagnetism and canted antiferromagnetic ordering of magnetic moments was observed in the samples x =1.5 and x = 2.0 respectively. The effect of variation of composition, frequency and temperature on the dielectric constant ( '), loss tangent (tan ) and conductivity ( ) has been carried out. The ac conductivity increased with temperature showing semiconductor like nature of the samples.

Summary: Thin films of high molecular weight PMMA, PVC and their blend were prepared with solution cast method. Further they were modified by adding Camphor Sulphonic Acid (CSA) to them. DSC studies indicate single glass transition temperature (Tg) for unmodified as well as modified blends indicating the miscibility of polymers. FTIR studies show the interaction between CSA-PVC, CSA-PMMA, CSA-(PVCþPMMA) blend. The D.C. electrical study was carried out at various temperatures from room temperature (307 K) to 373 K. After modification the variation of DC conductivity (s) is found to decrease in PVC and the PVC-PMMA blend whereas it is found to increase in PMMA with rise in temperature.

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