0000000000464960
AUTHOR
Henning Menzel
Complexes of an anionic poly(p-phenylene) polyelectrolyte and dioctadecylammonium bromide at the air–water interface
Abstract By spreading dioctadecyldimethylammonium bromide on a subphase containing rigid rod-like anionic poly( p -phenylene) sulfonate, a complex monolayer is formed in situ at the air–water interface. Complexation results in an increase of the area per amphiphile molecule compared to the amphiphile on pure water. The change in structural order upon complexation and subsequent compression of the monolayer can be demonstrated employing UV/Vis spectroscopy: A red-shift of the polymer absorption band upon compression and a subsequent partial reversion of this shift after monolayer collapse can be observed. The peak shift is discussed to be a result of the electronic interaction of the π -syst…
Mixed silane self assembled monolayers and their in situ modification
Mixed self assembled silane monolayers were prepared by coadsorption of Br and methyl terminated trichlorosilanes. By subsequent in situ modification the Br groups were converted into amino groups which can be used to tether polyglutamates to the surface. Here we describe the characterization of the monolayers by means of contact angle measurements and X-ray photoelectron spectroscopy (XPS). Both methods clearly indicate that the Br terminated silane is preferentially adsorbed from the solution. Following the in situ modification by XPS a yield of approximately 80% was determined for the substitution of the bromine by azide, whereas the yield for subsequent reduction to the amine is close t…