Surface structure of thin film blends of polystyrene and poly(n-butyl methacrylate)

in Colloid and Polymer Science (2000), 278(10), 993-999

Thin films of blends of polystyrene (PS) and poly(n-butyl methacrylate) (PBMA) were prepared by spin-casting onto silicon wafers in order to map the lateral distribution of the two polymers. The surfaces ... [more ▼]

Thin films of blends of polystyrene (PS) and poly(n-butyl methacrylate) (PBMA) were prepared by spin-casting onto silicon wafers in order to map the lateral distribution of the two polymers. The surfaces were examined by atomic force microscopy (AFM) secondary ion mass spectroscopy X-ray photoelectron spectroscopy (XPS) and photoemission electron microscopy (PEEM). Films with PBMA contents of 50% w/w or less were relatively smooth, but further increase in the PBMA content produced, initially, protruding PS ribbons and then, for PBMA ≥80% w/w, isolated PS islands. At all concentrations the topmost surface (0.5-1.0 nm) was covered by PBMA, whilst the PBMA concentration in the near-surface region, measured by XPS, increased with bulk content to eventual saturation. PEEM measurements of a PS-PBMA film at the composition at which ribbon features were observed by AFM also showed a PS-rich ribbon structure surrounded by a sea of mainly PBMA. [less ▲]

Surface composition of poly(styrene-d8-styrene) random copolymers studied by static secondary ion mass spectroscopy

in Macromolecules (1993), 26(20), 5400-5404

The surface compositions of a series of random copolymers of styrene and deuteriostyrene have been determined by SIMS. The mechanism of fragmentation during the SIMS process is examined, and the ... [more ▼]

The surface compositions of a series of random copolymers of styrene and deuteriostyrene have been determined by SIMS. The mechanism of fragmentation during the SIMS process is examined, and the contribution from naturally occurring isotopes is evaluated. The data are shown to fit a model of a completely random copolymer system if they are corrected for the effects of impurities introduced in the syntheses and for the contribution from C-13. [less ▲]