Morphologies in ternary polymer blends after spin-coating

The domain morphology of a polystyrene/poly(methyl methacrylate)/poly(2-vin ylpyridine) (PS/PMMA/ PVP) polymer blend was studied after spin-coating a f ilm from a common solvent. The strongly incompatible polymer mixture phase- separates during spin-coating. Atomic force microscopy, combined with selec tive dissolution of the different polymer phases was used to obtain informa tion on the polymer distribution in the film. By changing the relative comp osition of the mixture, a great variety of different morphologies was obser ved. The common feature of all observed morphologies is the compatibilizing function of poly(methyl methacrylate), which intercalates between the more incompatible polystyrene and polyvinylpyridine domains to prevent the form ation of high-energy interfaces.