Morphological Variation of an LB Film of Giant Amphiphiles Composed of Poly(ethylene oxide) and Hydrophobically Modified POSS.

Abstract

Hydrophobically modified polyhedral oligomeric silsesquioxanes (XPOSS) are linked to one end of water-soluble poly(ethylene oxide) (PEO) to synthesize giant amphiphiles (XPOSS-PEO). XPOSS-PEO exhibit an interesting surface activation capacity owing to the synergy of the soft PEO segment and hydrophobic XPOSS when they are spread on the water surface and compressed by the barrier. The monolayers of XPOSS-PEO at the air-water interface are transferred onto the silicon substrate at different surface pressures using the Langmuir-Blodgett (LB) film deposition protocol. The modification of the POSS head significantly changes the crystallinity of the PEO tail, which affects the LB film morphologies of the giant amphiphiles. When the POSS are modified with fluorinated agents, the assembled LB films show a fractal growth pattern, but when the POSS are decorated with a pure alkane chain, the fractal growth pattern does not present in the resulting LB film.