| Abstract
| - This study concerns the effects of temperature, compression rate, and packing density on conformationalproperties of polystyrene-block-poly(N-isopropylacryamide) (PS-b-PNIPAM) diblock copolymer monolayersat the air/water interface using the Langmuir balance technique. The dependency of surface pressure changeson temperature and compression rate is strongly influenced by the conformations of PNIPAM chains at theinterface, which can be adjusted by varying the packing density. Specifically, when loops or tails are formedat the interface, PNIPAM chains display thermosensitive properties due to hydration/dehydration and obviousdependence on compression rate. When PNIPAM chains take train conformation at the air/water interface,however, the surface pressure changes are nearly independent of temperature and compression rate becausealmost all segments of the PNIPAM chains are adsorbed at the interface and the nonpolar isopropyl groupsare preferentially oriented toward the air. Our work reveals that one could manipulate stimuli-responsiveproperties of PNIPAM chains at the interface simply by adjusting the conformations of PNIPAM chains.
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