2011 Volume 21 Issue 2 Pages 91-95
Structural change of a phase-separated block copolymer thin film with polystyrene (PS) and poly (2-vinylpyridine) (P2VP) in contact with different solvents was observed by in-situ neutron reflectometry using a conventional cell for a solid/liquid interface, and time evolution of phase-separated structure after a temperature jump to 200℃ was observed for diblock and triblock copolymer thin films of PS and P2VP by grazing-incidence small-angle X-ray scattering (GISAXS). When PS-P2VP diblock copolymer thin film was contacted with methanol and water, the structural change was induced by penetration of small amount of the solvent into the film, and the original structure was almost recovered after drying it. Also, the diblock copolymer thin film was easily dissolved into toluene, and the original structure was never recovered after the solvent contact. After the temperature jump the lateral correlation spots were evolved with a time in the GISAXS pattern similarly for either block copolymer thin film with spherical structure, though their as-spun states were different.
