Langmuir, Vol.21, No.23, 10324-10327, 2005
Flat orientation of hydrophobic cores induced by two-dimensional confinement of flexible bolaamphiphiles at the air-water interface
We designed and synthesized a new bolaamphiphile consisting of a biphenyl core, flexible trisiloxane spacers, and terminal ammonium groups. The compression of the trisiloxane-containing bolaamphiphile at the air-water interface led to the formation of monolayer films with the hydrophobic rigid core lying flat on the film surface. Such monolayer structures were formed through the compression-induced conformational change of the flexible bolaamphiphile from an extended state to a folded one as confirmed by surface pressure-area isotherm measurements, water contact angle measurements, atomic force microscopy, and LTV-vis spectroscopy.