1997 Volume 25 Issue 4 Pages 191-192
Damping functions in uniaxial, biaxial, planar extensions and shear deformation were calculated based on the Doi-Edwards theory. Planar extensional damping function has two components, hp1 and hp2 where the subscripts 1 and 2 stand for the stretching and restricting directions, respectively. Compared with the rigorous calculation, independent alignment approximation (IAA) works well except for hp2. In hp2, large difference between IAA and rigorous calculation appears. The calculated damping functions becomes approximately a universal function of the first strain invariant I except for hp2. On the other hand, compared at the same I, the experimental damping functions slightly deviate from each other. This deviation can be related to a difference in the magnitude of the second strain invariant II in different deformation fields.
