초록 |
The effect of core-shell polymer coated nanoparticles on block copolymer morphology is investigated systematically by controlling particle positioning within a block copolymer template. Our approach of varying the areal chain density of short thiol terminated polystyrene brushes on the particles is used to control the fraction of the particles adsorbed to the interface of PS-b-P2VP diblock copolymer domains. Interestingly, the addition of low volume fractions of the nanoparticle surfactants to lamellar diblock copolymers initially leads to a decrease in lamellar thickness, a consequence of decreasing interfacial tension. The relationship between domain spacing and morphology of block copolymer with the level of nanoparticle surfactants will be discussed based on a strong-segregation model. I thank my collaborators G. H. Fredrickson, J. Bang, C. J. Hawker, and E. J. Kramer. |