The transport of water and pentane vapor in Langmuir-Blodgett (LB)

No abstract

One of simplest Langmuir-Blodgett films is a stack of fatty acid layers bridged together by divalent cations. A certain fraction of fatty acids remain protonated, an amount dictated by aqueous subphase conditions during film deposition; these films are thus comprised of two components with different solubilities in organic solvents. We investigated the so-called skeletonization process that occurs when behenic acid multilayers are immersed in benzene. In particular, we used a quartz crystal microbalance to measure the loss of film mass and found that it agrees well with the amount of protonated acid in the original film. We also used the quartz crystal microbalance to investigate the equilibrium vapor sorption properties of unmodified films and compared them to those of skeletonized films. Both types of films take in nearly the same amount of water but absorb distinctly different amounts of selected organic vapors.