Controlled stress, oscillatory rheometry of mesophase-pitches Original Research Article

The rheology of mesophase-pitches, having different percentage mesophase content, has been investigated by means of controlled stress, oscillatory rheometry. Three thermally transformed mesophase-pitches (prepared from Ashland A240), with mesophase contents in the range 60–95%, together with a 100% optically anisotropic synthetic mesophase-pitch from Mitsubishi Gas-Chemical Company were studied. With the application of the time-temperature superposition principle, the viscoelastic behaviour of these mesophase-pitches was revealed in the form of the G′, G″, η′ and δ master curves.