Journal of Applied Polymer Science, Vol.124, No.4, 3302-3311, 2012
Blocked polyisocyanates containing fluorine atoms as crosslinking agents for polyurethane powder coatings
Using alicyclic diisocyanates (HDI, TMDI, IPDI, H12MDI), aliphatic unfluorinated and fluorinated alcohols, dibutyltin dilaurate as well as triethylamine as catalysts, blocked polyisocyanate crosslinkers for powder lacquers were synthesized. The chemical structure of these compounds was characterized by means of IR, 1H-NMR, 13C-NMR, and 19F-NMR spectroscopy. Their molecular weight distribution parameters were determined by gel permeation chromatography. These blocked polyisocyanates were used for the production of powder lacquer compositions and coatings. The three-dimensional surface topography and surface chemical structure of the resulting powder lacquers were investigated by means of confocal microscope and ATR FT-IR. The values of surface roughness parameters were calculated. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012