TY - JOUR
AU - Picci, Marie
AB - The potential for formulating low VOC, high performance, two-component waterborne isocyanate crosslinked coatings has generated a great deal of interest. The difficulties in formulating these coatings, however, are significant. A major problem associated with such systems is the isocyanate-water side reaction, which can lead to gassing/foaming, loss of isocyanate functionality, low gloss, and a reduced pot life. To compensate for this side reaction, these formulations usually contain a large excess of isocyanate. One novel approach to control the water side reaction is the use of catalysts which selectively catalyze the isocyanate-polyol reaction and not the isocyanate-water reaction. The selectivity of a variety of metal catalysts to catalyze the preferred reaction was measured using an FTIR method. A zirconium complex has shown unusually high selectivity for the isocyanate-polyol reaction in comparison to the standard dibutyltin dilaurate catalyst. This zirconium complex catalyst has been evaluated in several waterborne polyurethane formulations and has demonstrated less gassing/foaming, longer pot life, and higher gloss than dibutyltin dilaurate at equal cure time. The mechanism of catalysis and formulating techniques of this novel zirconium catalyst will be discussed.
TI - A selective catalyst for two-component waterborne polyurethane coatings
JF - Journal of Coatings Technology
DO - 10.1007/BF02697963
DA - 2007-08-29
UR - https://www.deepdyve.com/lp/springer-journals/a-selective-catalyst-for-two-component-waterborne-polyurethane-4Yu7DtI3dP
SP - 31
EP - 36
VL - 74
IS - 930
DP - DeepDyve
ER -