Sub‐glass‐transition temperature interface formation between an immiscible glass rubber pair

Abstract We used neutron reflectivity to measure the interfacial width in the immiscible system polystyrene/poly( n ‐butyl methacrylate) (PS/P n BMA). Measurements were made on the same samples at temperatures ranging from below the glass‐transition temperature ( T g ) of PS to slightly above. We observed significant broadening of the interface at temperatures below the T g of PS, indicating chain mobility below the bulk T g value. The …