ROLE OF COPOLYMER ARCHITECTURE ON ADSORPTION AT THE SOLID LIQUID INTERFACE/

The adsorption of monodisperse block copolymers comprising poly(ethyle ne oxide)-poly(butylene oxide) onto polystyrene latex from aqueous sol ution has been investigated by small-angle neutron scattering and phot on correlation spectroscopy with particular reference to the role of m olecular architecture. It appears that chain architecture is (i) a wea k factor in the adsorption behavior when the hydrophobic block is loca ted in the center of the polymer, since the triblock E100B15E100 behav ed very similarly to the cyclic c-E200B15, but (ii) a significant fact or when the hydrophobic block is located at the end of the copolymer c hain, as shown by the more dense and thicker layer formed by E200B15 c ompared to the triblock. E100B15E100 The hydrodynamic thickness of the layer formed by the small diblock E100B15 was approximately half that exhibited by the larger diblock E200B15. Good agreement was observed between depletion and SANS-derived adsorbed amounts. Theoretical predi ctions and self-consistent mean-field calculations of the adsorption a lso show excellent qualitative agreement with experiment.