Wirkstoff-Restgehalte verkapselter und freier Biozide in hydrophoben Fassadenbeschichtungen

Contents of encapsulated and non-encapsulated biocides in hydrophobic façade coatings.

The durability of the biocidal compounds Terbutryne (2-Methylthio-4-tert-butylamino-1,3,5-triazin), Diuron (DCMU, 3-(3,4-dichlorophenyl)-1,1-dimethylurea), IPBC (3-Iodoprop-2-ynyl-N-butylcarbamate), OIT (2-n-Octyl-isothiazolin-3-one) and DCOIT (4, 5-Di-chloro-2-n-octyl-isothiazolin-3-one) in a hydrophobic façade coating was examined in a several year weathering experiment. Biocide contents were determined in encapsulated and non-encapsulated form. For encapsulated biocides, the contents found in the coatings were higher than for non-encapsulated biocides. Hints indicating any migration processes of the biocidal active substances within the surface were not found. Considering the initial concentration, leaching of substances by driving rain and remaining contents in the coating after one year of weathering into a balance led to balance gaps of up to 64 %.