HR: 14:15h
AN: A53B-02    [Abstracts]
TI: Surface Partitioning and Stability of Mixed Films of Fluorinated Alcohols and Acids at the Air- Water Interface
AU: * Rontu, N A
EM: Nabilah.Rontu@colorado.edu
AF: University of Colorado at Boulder, Department of Chemistry and Biochemistry, Campus Box 215, Boulder, CO 80309, United States
AU: * Rontu, N A
EM: Nabilah.Rontu@colorado.edu
AF: CIRES, University of Colorado at Boulder, Campus Box 216, Boulder, CO 80309, United States
AU: Vaida, V
EM: Vaida@colorado.edu
AF: University of Colorado at Boulder, Department of Chemistry and Biochemistry, Campus Box 215, Boulder, CO 80309, United States
AU: Vaida, V
EM: Vaida@colorado.edu
AF: CIRES, University of Colorado at Boulder, Campus Box 216, Boulder, CO 80309, United States
AB: The production of fluorinated compounds over the past 50 years has had numerous industrial applications. For example, perfluorinated carboxylic acids are used in the synthesis of polymers and fire retardants, perfluoroalkyl sulfonates act as surface protectors, and fluorotelomer alcohols are incorporated into products such as paints, coatings, polymers, and adhesives. Fluorotelomer alcohols (FTOHs) are linear polyfluorinated alcohols with the formula CF₃(CF₂)_nCH₂CH₂OH (n=1,3,5,…). They have been suggested as possible precursors for perfluorinated carboxylic acids and detected in the troposphere over several North American sites. Perfluorocarboxylic acids have even been detected in the arctic food chain, human blood, tissues of animals and environmental waters. We report the surface activity of fluorotelomer alcohols and perfluorinated carboxylic acids at the air-water interface by using a Langmuir trough. Isotherms of the pure compounds along with mixed films with other organic carboxylic acids were collected. The main objective of these experiments was to understand their heterogeneous chemistry by characterizing the pure and mixed films, which serves as a representative model for organic films on atmospheric surfaces such as those found on oceans and aqueous aerosols. Film properties and behavior, notably stabilization, evaporation from the subphase, and miscibility in the single-component mixtures as well as in the mixed films will be discussed. An important consequence of FTOHs and perfluorocarboxylic acids being found to partition to the air-water interface is the possibility of their transport and widespread distribution and deposition using atmospheric aerosols.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0315 Biosphere/atmosphere interactions (0426, 1610)
DE: 0368 Troposphere: constituent transport and chemistry
DE: 4801 Aerosols (0305, 4906)
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly