- Author
- Sung, L. P. | Karim, A. | Douglas, J. F. | Han, C. C.
- Title
- Dimensional Crossover in the Phase Separation Kinetics of Thin Polymer Blend Films.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Journal
- Physical Review Letters, Vol. 76, No. 23, 4368-4371, June 3, 1996
- Distribution
- FOR MORE INFORMATION CONTACT: URL: http://link.aps.org/abstract/PRL/v76/p4368
- Keywords
- kinetics | polymer blend films
- Abstract
- The kinetics of phase separation in thin polymer blend films of polystyrene and polybutadiene on a silicon substrate is examined by optical microscopy of the free film boundary. Our observations on 1000 and 200 films are consistent with a crossover from three- to two-dimensional spinodal decomposition kinetics in the (off-critical) viscous hydrodynamic regime. In this stage of phase separation the exponent n, characterizing the scale R(t)~tn of the coarsening pattern, is predicted to change from 1 to a value near 0.46 upon lowering the dimensionality.