The response of pristine and doped poly(p-phenylene sulfide) towards MeV gamma photons

The effect of γ-photons on the potential engineering thermoplastic poly(p-phenylene sulfide) (PPS) has been investigated. The structural modifications are studied by elemental analysis, Rutherford back Scattering, Fourier transform infrared spectroscopy and differential scanning calorimetry. The polymer is resistant to irradiation up to a maximum dose of 540 kGy. Introduction of KBr that undergoes photo-decomposition resulted in disruption of the aromaticity of the polymer moiety with possible introduction of extensive cross-linking. Evidence for this structural modification was obtained from a decrease in the melting point from the differential scanning calorimetry profile and from FTIR spectral features with complete disappearance of the characteristic aromatic skeletal vibration bands at 1467 and 1379 cm-1 and with reduced band intensity for the in- plane and out-of-plane C-H bending modes and aromatic thio-ether linkage at 1008 and 1088 cm-1 respectively.