Viscoelastic effects on the phase separation of polymer blends
- Univ. of Leeds (United Kingdom)
- Imperial College, London (United Kingdom)
We have observed unusual behaviour in the phase separation dynamics in PS/PVME polymer blends, in which the PS component is highly entangled. To account for this theoretically, we modify the Cahn-Hilliard theory of concentration fluctuation dynamics to include the short time network-like nature of high molecular weight polymers. We propose an additional term in the free energy, due to elastic energy arising from the finite lifetime of entanglements. If we assume a single exponential decay time for the entanglements, the equation of motion is governed by two exponential modes. For quenches into the two phase region, the faster mode always decays with time, and the slower mode grows. The extent to which the theory agrees with experimental results is discussed.
- OSTI ID:
- 603000
- Report Number(s):
- CONF-961108-; TRN: 98:001968-0098
- Resource Relation:
- Conference: Annual meeting of the American Institute of Chemical Engineers (AIChE), Chicago, IL (United States), 10-15 Nov 1996; Other Information: PBD: 1996; Related Information: Is Part Of 1996 First joint topical conference on processing, structure and properties of polymeric materials; PB: 594 p.
- Country of Publication:
- United States
- Language:
- English
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