| Titre : |
Star oligomers for low VOC polyurethane coatings |
| Type de document : |
texte imprimé |
| Auteurs : |
J. Huybrechts, Auteur ; K. Dusek, Auteur |
| Année de publication : |
1998 |
| Article en page(s) : |
p. 117-127 |
| Note générale : |
Bibliogr. |
| Langues : |
Anglais (eng) |
| Index. décimale : |
667.9 Revêtements et enduits |
| Résumé : |
Hydroxyl functional star oligomers prepared by ring-opening polycondensation have a narrow molecular weight and composition distribution. Such oligomers give a solids/viscosity advantage over linear structures at the same molecular weight and can be used in low VOC two component polyurethane coatings. The solids/viscosity advantage is a combination of the highly branched structure and the narrow molecular weight distribution. Acrylic polyols formulated at the same molecular weight/polarity/average functionality and hydroxyl value give poorer drying properties. This difference can be explained by the fact that the free radical polymerisation technique leads to polymer compositions having a broad molecular weight and functionality distribution and high fractions of polymer with a low functionality. The potlife of acrylic polyols based formulations is adversely affected by the higher fractions of high molecular weight material and with a high average functionality. In low VOC polyurethane formulations star oligomers need to be formulated within a narrow range of compositions (TG, polarity), functionality and molecular weight to get an optimum balance of drying properties and potlife. |
| Note de contenu : |
- HYDROXYL FUNCTIONAL (METH)ACRYLATE COPOLYMERS - FREE RADICAL POLYMERISATION
- HYDROXYL FUNCTIONAL (METH)ACRYLATE COPOLYMERS - GROUP-TRANSFER POLYMERISATION
- FILM FORMATION AND CROSSLINKING IN TWO COMPONENT POLYURETHANE COATINGS
- STAR AND HYPERBRANCHED POLYMERS
- RESULTS AND DISCUSSION : Synthesis - Solids-viscosity relation of linear against star structures - Drying-potlife of a linear acrylic against a star oligomer - Effect of star oligomer structure on drying properties |
| Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=16475 |
in SURFACE COATINGS INTERNATIONAL > Vol. 81, N° 3 (03/1998) . - p. 117-127
Aller sur edunet
Accueil
Star oligomers for low VOC polyurethane coatings in SURFACE COATINGS INTERNATIONAL, Vol. 81, N° 3 (03/1998)
