[article]
| Titre : |
A selective catalyst for two-component waterborne polyurethane coatings |
| Type de document : |
texte imprimé |
| Auteurs : |
Z. Alex He, Auteur ; Werner J. Blank, Auteur ; Marie E. Picci, Auteur |
| Année de publication : |
2002 |
| Article en page(s) : |
p. 31-36 |
| Note générale : |
Bibliogr. |
| Langues : |
Américain (ame) |
| Tags : |
Etude expérimentale Zirconium Complexe Catalyseur Adjuvant Formulation Peinture eau Uréthanne polymère deux constituants Matériau revêtement |
| Index. décimale : |
667.9 Revêtements et enduits |
| Résumé : |
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. |
| Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=5644 |
in JOURNAL OF COATINGS TECHNOLOGY (JCT) > Vol. 74, N° 930 (07/2002) . - p. 31-36
[article]
|
Aller sur edunet
Accueil
A selective catalyst for two-component waterborne polyurethane coatings in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 74, N° 930 (07/2002)
