Thesis (Ph.D.) - Cairo University - Faculty of Science - Department of Physics

A variety of experimental techniques is employed to draw a consistent picture of the physical properties of PVC/PMMA loaded with different concentrations of conductive PPy nano filler. Electrical, mechanical, and thermal behaviors of such materials were investigated. DSC thermograms of native composites were plotted. One Tg is displayed for blend and this indicates the homogeneous behaviour of it. The weight losses for samples starts at approximately 200{u1D52}C and end at 370 {u1D52}C and the final weight loses of 47%-63% is detected. The addition of conductive polypyrrole particles shifts the two peaks of XRD toward higher 2{u04E8} values which confirm the complete mixing of this filler with PVC and PMMA matrices. The dielectric constants were measured. The experimental dielectric constant values were compared with four models and found that the model offered by Ezzat et al fit well. The mechanical properties (Young's modulus) are obviously improved by the addition of conductive PPy. Both {u0190}' and vac obviously increase after ion implantation. The irradiation at 4.87x10¹⁴ ions cm⁻² increases vac of sample PVC/PMMA loaded with 3 wt. % PPy by 3 orders of magnitude. Br ion fluences change the type of conduction mechanism for samples pure PVC/PMMA at different fluences, 1 wt. %, and 2 wt. % at 5.95x10¹⁴ ions cm⁻²

Issued also as CD