Fluorescence scanning near-field optical microscopy of conjugated polymer blends

Fluorescence scanning near-field optical microscopy with a spatial resoluti on of similar to 150 nm is used to investigate blends of conjugated polymer s in a poly(methylmethacrylate), PMMA, matrix. These blends, which phase se gregate on a length scale of several hundred nanometers, have a high degree of correlation between their fluorescence and topographic images, as illus trated by measurements taken from a sample of 5% by weight of poly(2-methox y-5-(2',6'-dimethyloctyloxy)-pphenylenevinylene), "OC1C10" PPV, in PMMA. In a blend containing both poly(2,5-dihexyloxyp-phenylenevinylene), CN-PPV, a nd poly(2-dimethyloctylsilyl-p-phenylenevinylene), DMOS-PPV, spectroscopic contrast was used to identify material both on the surface and buried withi n a thin transparent film. (C) 1999 American Institute of Physics. [S0003-6 951(99)02937-X].