Topography and composition images of model thin films of deuterated polystyrene (dPS) and polyisoprene with different blend compositions were analyzed with an extension of integral-geometry approach. Surface patterns, formed in the course of spin-casting from toluene onto self-assembled monolayers (SAM), were recorded with scanning force microscopy. Their relation with lateral phase domain structures was demonstrated by dynamic secondary ion mass spectrometry, yielding maps of dPS distribution. Morphological measures, which cannot be provided by Fourier transform analysis (FTA), characterize individual images, compositional series of the surface patterns and individual features of the patterns. Different morphologies (nucleation-and spinodal-type and hole-and island-dominated ones) are consistently characterized by the Minkowski measures and related parameters. For instance, the latter can measure circular character of the individual features and estimate dominant lateral length (determined rigorously with FTA). Lateral morphologies are hardly affected when CH3-terminated SAM is exchanged for SAM with COOH end groups.

Sectional views of thin films of symmetric polystyrene/polyisoprene (PS/PI) blends spin-cast from toluene (C6H5CH3) onto CH3- and COOH-terminated self-assembled monolayers (CH3−SAM and COOH−SAM) show concave- (sharp-edged) and convex-shaped (round) protrusions, respectively, while other morphology features are identical. A 3-dimensional phase domain arrangement was determined with spectroscopic techniques (profiling and mapping mode of dynamic secondary ion mass spectrometry, dSIMS, and X-ray photoelectron spectroscopy). Surface topography was examined with atomic force microscopy and monitored, during the dSIMS analysis, with secondary electrons. In addition, solvent evaporation from PS, PI, and PS/PI layers cast on CH3−SAM and COOH−SAM was determined. The collected data were used to put forward a model of morphology formation and to elucidate the role of evaporation speed dependent on substrate chemistry in this process, demonstrated here for the first time.

Blends of poly(2-vinylpyridine), polystyrene, and poly(methyl methacrylate) of four different compositions (2:3:0, 3:2:0, 1:1:0, and 2:2:1 w:w:w) were spin-cast onto periodically (λ = 4 μm) patterned substrate (with two alternating stripes:  Au attracting PVP and neutral self-assembled monolayer), and resulting film morphologies (with inherent domain scale 0.2 λ ≤ R < 1.8 λ) were recorded with scanning force microscopy and examined with Fourier transform analysis and the integral geometry approach. The morphologies depend on not only spatial (R/λ) but also compositional commensuration between blends and symmetric pattern:  λ/2-substructures are present, in addition to λ-structures, for isolated (2:3:0) but not for continuous (3:2:0) PVP domains. This explains also the data for 1:1:0 blends which present a transition from isolated to continuous PVP domains (for larger R values). In turn, interfacial compatibilizer (PMMA in 2:2:1) results in the well-ordered λ/2-substructures for both morphology types.

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Film blends of poly(3-butyltiophene-2,5-diyl) (PT) and polystyrene (PS; 1 : 1 w/w) were spin-coated onto silicon wafers from chloroform, tetrahydrofuran, and cyclohexanone at a controlled relative humidity between 4 and 86%. The film morphologies were determined with atomic and lateral force microscopy and mapping and depth profiling modes of dynamic secondary-ion mass spectroscopy. Independently, white light interferometry was used to examine the expansion and response time (t) of pure polymer layers exposed to solvent vapors and moisture. The higher PS solubility, in comparison with the PT solubility, in chloroform and tetrahydrofuran resulted in PS/PT//Si bilayers, which were the final structures for coatings from chloroform [with much larger t(PS)/t(PT) ratios]. For tetrahydrofuran, these bilayers were destroyed, most likely by surface and interface instabilities, yielding hierarchic lateral structures. For cyclohexanone (with the largest t values), a large-scale component of the lateral structures was absent, and this suggested the leveling of surface instabilities. The humidity changed the structural scales and thickness of the films cast from tetrahydrofuran (because it had the best solubility with water). The humidity effects of chloroform and cyclohexanone [reported earlier for polyaniline and poly(vinyl pyridine) blends] were practically absent. Moisture was not easily absorbed by PT and PS [in contrast to polyaniline and poly(vinyl pyridine)] and probably adsorbed merely at the surfaces of blend films rich in tetrahydrofuran.