Molecular aggregation states of silsesquioxane-terminated polystyrene in polystyrene thin film

Organic-inorganic hybrid polymers (PS-POSS), which were polystyrene (PS) with polyhedral oligomeric silsesquioxane (POSS) end group, were prepared by nitroxide-mediated radical polymerization. Blend films composed of PS-POSS and PS were spin-coated from their toluene solution onto cleaned silicon wafer. The dispersibility of POSS in PS thin films was improved by the introduction of POSS as the chain end groups of PS. The addition of PS-POSS to PS thin film can stabilize the film against dewetting. Neutron reflectivity measurements revealed that PS-POSS formed enriched layer at the surface and interface of the film. The segregation of the PS-POSS, which changes the surface and interface free energy of the film, can be an important factor in the dewetting inhibition effect.