Rheological study of some epiclon-based polyimides

The rheological properties of new partially aliphatic polyimides in NN-dimethylformamide were investigated at different concentrations and temperatures comparatively to their corresponding poly(amic acid)s. The rheological junctions,i.e., dynamic viscosity, shear rate, elastic shear modulus, and viscous shear modulus, and the parameters obtained from rheological properties such as apparent energy of activation and flow activation entropy reflect the influence of the diamine chemical structures used in the synthesis process.