We report studies of the self-assembly of amphiphilic diblock copolymers, p
olystyrene-b-poly(alkyl acrylate) at the air water interface. Using the Lan
gmuir film balance, unusual multiple plateau/inflection transitions in surf
ace pressure / molecular area isotherms have been observed. Transmission el
ectron microscopy of the corresponding Langmuir-Blodgett films has shown th
e presence of surface micelles. We have studied the effect of a range of di
fferent alkyl blocks on the isotherms. Possible mechanisms for the multiple
inflections observed in the isotherms are discussed. (C) 1999 Elsevier Sci
ence S.A. All rights reserved.