Abstract
It is well known that in amorphous polymer the distribution curve of relaxation time of stress is depicted as a continuous spectrum of the "wedge" part and the "box" part. The "box" part is dependent on such factors as molecular weight and its distribution, branching, composition etc. We have attempted, therefore, to study the relation between the structure of polymer and its viscoelastic properties.
The master curve obtained and relaxation spectra calculated from it changed remarkably with the composition of random copolymers. In the "wedge" part, this is due to the flexibility of the polymer chain, and the slope approaches 1/2 with increase in the composition of MMA. Of the "box" part, the values of various kinds of parameter from Procedure X (for example, τm, ηt, Je etc.) were calculated. The relation between τm, ηt and polymer composition showed remarkable phenomena. This seems to be due to the inter-molecular dilution effect by the MA that constitutes the other side of the random copolymers. The relaxation time was observed to have a tendency of shifting to the side of MA.
