Localization of a homopolymer dissolved in a lamellar structure of a block copolymer studied by small-angle neutron scattering

The localization of deuterated styrene homopolymer dissolved in a lamellar structure of a styrene-2-vinylpyridine diblock copolymer was studied in comparison with that of the end part of the block copolymer by observing diffraction from the styrene and 2-vinylpyridine microdomains of deuterated styrene homopolymer/styrene-2-vinylpyridine diblock copolymer blends by SANS. From the diffraction profiles in SANS and the dependence of domain spacing on the volume fraction of the styrene homopolymer, it was found that the homopolymers are isolated in the middle of the polystyrene domain, though they are concentrated less than the end parts of the block chains