Suppression of Phase Separation Pattern Formation in Blend Films With Block Copolymer Compatibilizer.
Suppression of Phase Separation Pattern Formation in
Blend Films With Block Copolymer Compatibilizer.
Sung, L. P.; Douglas, J. F.; Han, C. C.; Karim, A.
Journal of Polymer Science: Part B: Polymer Physics,
Vol. 41, No. 14, 1697-1700, July 15, 2003.
copolymers; thin film; polymer blend; phase separation;
surfactant; surface pattern formation; block copolymer;
The structure of thin films is sensitive to
surface-tension variations that can cause the free
surface of films to buckle.14 Many different types of
film perturbations cause surface-tension variations and
thus film-surface pattern formation. Recent studies2,3
have shown that phase separation within very thin
polymer blend films leads to a range of surface patterns
(bumps, holes, and labyrinthine ridges and valleys) that
depend on the polymer composition. These patterns
disappear when the films are returned into the one-phase
region of the fluid mixture, verifying their
phase-separation origin. 2,3 Although in some situations
the surface patterns are beneficial, the surface
patterns can sometimes compromise film-barrier
properties or create other undesirable changes in
polymer-coating properties (optical appearance,
friction, tendency to attract impurities from the
atmosphere, etc.). This technological problem led us to
seek methods of inhibiting surface-pattern formation in