Published online by Cambridge University Press: 25 February 2011
The polymer blend system of deuterated polystyrene (PSd) and the statistical copolymer poly(styrene-co-para-bromo-styrene) (PBrxS) is partially compatible or incompatible depending on the degree of bromination x. The width of the interface in a bilayer system can thus be controlled in a wide range by an adjustment of x. This is demonstrated in neutron reflectivity experiments where the interfacial width is measured with an accuracy better than lnm. The interface width depends strongly on compatibility as expressed by the Flory-Huggins interaction parameter x- Results are compared with current theories.