S. Affrossman et al., SURFACE-TOPOGRAPHY AND COMPOSITION OF DEUTERATED POLYSTYRENE-POLY(BROMOSTYRENE) BLENDS, Macromolecules, 29(14), 1996, pp. 5010-5016
Surface structure, obtained from atomic force microscopy and X-ray ref
lectivity, and surface chemical analysis data, obtained from X-ray pho
toelectron and static secondary ion mass spectroscopy, are reported fo
r blends of poly (p-bromostyrene) with poly(deuteriostyrene). When hig
h speeds are used in the spin-coating process, the atomic force micros
copy measurements reveal that the surface structure consists of island
s, the distribution and number changing with the poly(bromostyrene) co
ntent. A ribbon structure is observed at just above 50% (w/w) poly(bro
mostyrene) in the mixture. These ribbons merge to form more continuous
structures, leaving voids at higher concentrations. X-ray reflectivit
y data from the films were consistent with the topographical features
observed with the AFM. At low spinning speeds, continuous films with l
ittle or no topographical structure are formed. The islands observed a
t high spinning speeds are predominately poly(bromostyrene) and reflec
t the importance of thermodynamic and kinetic driving forces in their
formation.