- 466 Downloads
The linear viscoelasticity of a polymer is uniquely described by the classical theory of linear viscoelasticity. Material properties are contained in the relaxation time spectrum which depends on the molecular details. To address an unsolved problem in rheology, the search for relations between molecular architecture and relaxation, we propose to start out with the most simple molecular architecture and later add molecular details. This proposal bases on the observation that polymers with the mostt simple geometry (long linear flexible chains of uniform length) relax with a universal relaxation time spectrum which is self-similar. Its parameters are a generic expression of chain flexibility, rotational energies of the chemical bonds, atomic masses involved in the molecular motion, molecular interaction forces, etc. of the chemical building blocks. We assume that these generic parameters can be considered fixed for each chemistry and that only few new parameters have to be added when proceeding to architectures which are branched or distributed in size (polydisperse). In a similar fashion one may add specific effects of solvents, molecular interactions, or phase transition (not elaborated here). Generic parameters are given for polystyrene, a polybutadiene, and a polyvinylmethylether.
KeywordsRelaxation Modulus Relaxation Mode Linear Viscoelasticity Longe Relaxation Time Small Amplitude Oscillatory Shear
Unable to display preview. Download preview PDF.
- Bird RB, Armstrong R, Hassager O, Curtiss CF (1987) Dynamics of Polymeric Liquids, Vol. 2, J. Wiley, New YorkGoogle Scholar
- de Gennes PG (1979) Scaling Concepts in Polymer Physics, Cornell University Press, IthacaGoogle Scholar
- Doi M, Edwards SF (1986) The Theory of Polymer Dynamics Clarendon Press, OxfordGoogle Scholar
- Ferry JD (1980) Viscoelastic Properties of Polymers. 3rd ed. Wiley, New YorkGoogle Scholar
- Graessley WW (1974) The entanglement concept in rheology Adv. Polym. Sci. 16, Springer Verlag HeidelbergGoogle Scholar
- Granick S, Reiter G, Demirel L, Cai L, Reanasky J (1993) Presentation at 2nd Int. Discussion Meeting on Relaxation in Complex Systems, 28/6–8/7/93, Alicante, Spain.Google Scholar
- Jackson J, Winter HH (1994) Entanglement and flow behavior of bidisperse blends of polystyrene and polybutadiene Macromolecules under reviewGoogle Scholar
- Kimura S, Osaki K, Kurata M(1981) J. Rheology 32, 151Google Scholar
- Koppi KA, Tirrell M, Bates FS, Almdal K, Colby RH (1992) Lamellae orientation in dynamically sheared diblock copolymer melts. J. Phys. II France 2, 1941:1959Google Scholar
- Plazek DJ (1966) J. Polymer Sci. A-2, 745Google Scholar
- Tobolsky AV (1960) Properties and Structures of Polymers, Wiley New YorkGoogle Scholar
- Winter HH, Baumgärtel M, Soskey P (1993) A parsimonious model for viscoelastic liquids and solids, in A. A. Collyer, Ed. Techniques in Rheological Measurement, Chapman & Hall, LondonGoogle Scholar