TIT# Structure and Properties of Oil Extended Styrene Butadiene Block
     Copolymers
AUT# Polizzi, S.; Stribeck, N.; Zachmann, H. G.; Bordeianu, R.
SOU# Polymer Composites (1988), 9(6), 434-442
LOC# xv004  @selbst.ftx
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ABS# The relationships between mechanical properties and structure of rapidly
     spin cast styrene-butadiene-styrene (SBS) block copolymers diluted with
     two different types of mineral oil are discussed. Small angle X-ray
     scattering (SAXS) measurements indicate that both oils go mainly into the
     rubbery polybutadiene phase. While during rapid spin casting the
     paraffinic oil improves the phase separation of polystyrene (PS) and
     polybutadiene (PB), the opposite is true for the aromatic oil. The
     measurements also suggest that the oils cause a preferential swelling of
     the superstructure along the longitudinal direction of the cylindrical
     PS domains. From this, it can be concluded that a larger number of
     interconnecting PB chains is present in the cross direction than in the
     longitudinal one. With increasing oil content, a further decrease of
     interconnecting chains in the latter direction may be the reason for
     the decrease of the tensile modulus. Furthermore, above a critical value
     of dilution (33 wt percent for paraffinic oil, 50 wt percent for the
     aromatic one), more and more spherical domains are formed instead of the
     cylindrical ones. This morphological transition explains the step present
     in the double logarithmic plot of the large strain tensile modulus as a
     function of oil dilution.