| Titre : |
Hydrophilic polyisocyanates : the best balance between performance and environmental concern |
| Type de document : |
texte imprimé |
| Auteurs : |
Philippe Olier, Auteur |
| Année de publication : |
2015 |
| Article en page(s) : |
p. 75-80 |
| Note générale : |
Bibliogr. |
| Langues : |
Anglais (eng) |
| Catégories : |
Essais d'adhésion
Formulation (Génie chimique)
Polyisocyanates hydrophiles
Réticulants
Revêtements bi-composant:Peinture bi-composant
Revêtements en phase aqueuse:Peinture en phase aqueuse
|
| Index. décimale : |
667.9 Revêtements et enduits |
| Résumé : |
It is no secret today that the quest for more environmentally friendly and healthier products is a key preoccupation among a lot of chemical companies. In many cases, regulation constraints have led to reconsider bath technologies and products but certainly not performances.
Coatings particularly is one field in which high performance is required since the function of a coating, outside of the aesthetics, is mainly to protect the substrate it is applied on. Polyurethane coatings, especially two components systems, are very appreciated for their outstanding performances, especially durability and outdoor weatherability. When health and environmental preoccupations started to be at the forefront, 2K polyurethane waterborne coatings became naturally a route to follow, especially to reduce Volatile Organic Compounds (VOC) in the formulations.
The challenge was above all to design waterborne formulations containing polyisocyanates which would be stable, regarding the reaction with water. Such a formulation should provide enough time to enable application and film formation with good end properties. Hydrophilic polyisocyanates were the answer and many synthesis routes were tried, each one having of course, advantages and drawbacks.
In this paper, we will present a study aiming to highlight differences regarding the nature of the hydrophilic polyisocyanates. Latest developments of Vencorex in this field will be also included. |
| Note de contenu : |
- POLYISOCYANATE : HOW TO MAKE IT HYDROPHILIC ?
- EXPERIMENTAL : Hardeners - Starting point formulations
- RESULTS : Emulsification ability - Application properties
- TABLES : 1. Solubility parameters of hexamethylene trimer or biuret - 2. Characteristics of the hardeners - 3. Formulations - 4. Evaluation of adhesion with cross hatch and tape adhesion test
- FIGURES : 1. : Particle size distribution of Easaqua XL 600 and polyisocyanate 1 into water - 2. Visual aspect of formulations regarding the mixing time and the nature of the polyisocyanate - 3. VOC, gloss and Koenig hardness of coatings made with Easaqua XL 600 and polyisocyanate. 1. Polyisocyanate 1 contains 20% solvent - 4. Contact angle of a drop of water with the surface. High angle values indicate hydrophobic surfaces. Angle values over 90° are the sign that the liquide does not wet the substrate - 5. Contact angle measurement of water on 2K waterborne coatings (initial and after 3 days at 100% RH and 50°C - 6. Visual aspect of the coatings after crosshatch and tape adhesion test - 7. Visual aspect of coated panels after 350 hours of salt spray test |
| En ligne : |
https://drive.google.com/file/d/1mWEEPsgKAs7RQgi3rIxpy7dCyWmc-YoP/view?usp=drive [...] |
| Format de la ressource électronique : |
Pdf |
| Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=24150 |
in PAINTINDIA > Vol. LXV, N° 3 (03/2015) . - p. 75-80
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Hydrophilic polyisocyanates : the best balance between performance and environmental concern in PAINTINDIA, Vol. LXV, N° 3 (03/2015)
