Langmuir, Vol.14, No.7, 1779-1785, 1998
Role of copolymer architecture on adsorption at the solid/liquid interface
The adsorption of monodisperse block copolymers comprising poly(ethylene oxide)-poly(butylene oxide) onto polystyrene latex from aqueous solution has been investigated by small-angle neutron scattering and photon correlation spectroscopy with particular reference to the role of molecular architecture. It appears that chain architecture is (i) a weak factor in the adsorption behavior when the hydrophobic block is located in the center of the polymer, since the triblock E100B15E100 behaved very similarly to the cyclic c-E200B15, but (ii) a significant factor when the hydrophobic block is located at the end of the copolymer chain, as shown by the more dense and thicker layer formed by E200B15 compared 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 predictions and self-consistent mean-field calculations of the adsorption also show excellent qualitative agreement with experiment.
Keywords:ANGLE NEUTRON-SCATTERING;BLOCK-COPOLYMERS;NONSELECTIVE SOLVENT;POLY(ETHYLENE OXIDE);AQUEOUS-SOLUTION;LAYER THICKNESS;ETHYLENE-OXIDE;BUTYLENE OXIDE;POLYMERS;DIBLOCK