We have studied the dynamic scanning of liquid-crystalline(LC) poly( p-phenyleneterephthalamide) sulfuric acid (PPTA-H 2SO 4) solution, and its blend with single-walled carbon nanotubes (SWNTs), by using a flat plate rotational rheometer. The effects of weight concentration and molecular weight of PPTA, as well as operating temperature, on dynamic viscoelasticity of the PPTA-H 2SO 4 LCsolution system are discussed. The transition from a biphasic system to a single-phase LC occurs in the weight concentration range of SWNTs from 0.1% to 0.2%, in which complex viscosity reaches the maximum at 0.2 wt% and the minimum at 0.1 wt%, respectively, of SWNTs. With increasing SWNT weight concentration, the endothermic peak temperature increases from 73.6 to 79.9 °C. The PPTA/SWNT/H 2SO 4 solution is in its plateau zone and storage modulus ( G′) is a dominant factor within the frequency ( ω) range of 0.1–10 rad/s. As w increases, the G′ rises slightly, in direct proportion to the w. The loss modulus ( G′′) does not rise as a function of ω when ω < 1 s ？1, then when ω > 1 s ？1 G′′ increases faster than G′, yet not in any proportion to the ω.
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