Modification of Polymer Composite by Proton Beam Irradiation

Composite films of the thermoplastic polymer (Polymethyl methacrylate) filled with different concentration of organometallic compound was prepared by chemical method. These films were irradiated with 3 MeV proton beam at the fluences of 6×1012 and 1×1013 ions/cm2. The dependence of a.c. conductivity of pristine and irradiated films on frequency, fluence of proton beam, and filler concentration was studied. The result shows that the conductivity increases with increase in the concentration of the filler and also with fluence. Microhardness of the films was studied for the applied load ranging from 10–1000 mN. The hardness is observed to increase with the fluence. This may be due to the conversion of polymeric structure in to hydrogen depleted carbon network, which makes polymer more conductive and harder. Surface morphology was studied by means of atomic force microscopy (AFM). It reveals that the average surface roughness decreases after irradiation. Structural changes in the polymer structure due to irradiation have been studied using Fourier Transform Infrared (FTIR) spectroscopy.