title: Leaching of biocides from polymer renders under wet/dry cycles--Rates and mechanisms.
abstract: In this study it was tested, which mechanism for the transport of biocides in polymeric renders is more relevant: (1) evaporative transports (meaning there is a flow of water through the material due to evaporation on the surface), which transports also the biocides to the surface, (2) transport through the polymer and (3) transport through water filled pores. It turned out that under the experimental conditions evaporative transport was not relevant, while transport through soaked (constantly wetted) renders was considerably faster than by other means. Additionally it turned out that also the equilibria were influenced by the water content. Differences in equilibria can be up to factor 10 between constantly wetted (soaked) and un-wetted materials. The two tested materials (one silicone and one acrylate render) had significantly different leaching behavior concerning equilibria and dynamics of mass flows, but for both the pre-wetted materials leached most.
authors.affiliation: AGH University of Science and Technology, Department of Coal Chemistry and Environmental Sciences, Al. Mickiewicza 30, 30-059 Krakow, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Styszko
authors.affiliation: Environmental Science, Aarhus University, Frederiksborgsvej 399, 4000 Roskilde, Denmark.
authors.forename: Ulla E
authors.initials: UE
authors.lastname: Bollmann
authors.affiliation: Environmental Science, Aarhus University, Frederiksborgsvej 399, 4000 Roskilde, Denmark. Electronic address: kb@dmu.dk.
authors.forename: Kai
authors.initials: K
authors.lastname: Bester
mesh_terms: D000179:Acrylates / Q000737:chemistry; D004202:Disinfectants / Q000032:analysis / Q000737:chemistry*; D007700:Kinetics; D011108:Polymers / Q000737:chemistry*; D012828:Silicones / Q000737:chemistry; D013499:Surface Properties; D014835:Volatilization; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*
chemical_list: D000179:Acrylates; D004202:Disinfectants; D011108:Polymers; D012828:Silicones; D014874:Water Pollutants, Chemical; D014867:Water; C036658:acrylic acid
keywords: Biocides; Desorption; Leaching; Render; Wet and dry cycles