Titre : |
Synthesis and properties of multiarm star hydroxyl-terminated polyesters for two-component polyurethane coatings |
Type de document : |
texte imprimé |
Auteurs : |
Shan Huang, Auteur ; Juan Xiao, Auteur ; Yan'an Zhu, Auteur ; Jinqing Qu, Auteur |
Année de publication : |
2017 |
Article en page(s) : |
p. 505-516 |
Note générale : |
Bibliogr. |
Langues : |
Américain (ame) |
Catégories : |
Essais (technologie) Groupe hydroxyle Polyesters Polymères -- Synthèse Polymères ramifiés Polyuréthanes Rhéologie Stabilité thermique Vernis -- Propriétés mécaniques Vernis bi-composant
|
Index. décimale : |
667.9 Revêtements et enduits |
Résumé : |
A series of multiarm star hydroxyl-terminated polyesters (MHPs) were synthesized through a “one-pot” method with di-trimethylolpropane as the core molecule, 2,2-dimethylolpropionic acid as the AB2-type monomer, ε-caprolactone, and monocarboxylic acids as modifiers. The influence of different monocarboxylic acids on the viscosities of polyesters and their 2K-PU films hardness was studied and it was found that MHPs prepared from lauric acid displayed the higher films hardness and lower viscosities. IR spectra of MHPs disclosed the ring-opening reaction between ε-caprolactone and hydroxyl groups occurred. 1H NMR spectra demonstrated that the molecular structures of MHPs were irregular due to the multiplicity of reaction processes. The measured number-average molecular weights (Mn) of MHPs were around 715–1854 g/mol with the PDI of 1.45–2.05. MHPs exhibited lower viscosities in the range of 3304–9060 mPa s at 100% solid contents and possessed lower intrinsic viscosities compared with linear polymers of similar molecular weight. The cured films of MHPs exhibited excellent impact resistance, adhesion, flexibility, and high hardness and displayed good thermal stability with 5% weight loss at 280°C. The solution viscosities of MHPs were less than 450 mPa s at 80% solid contents, and the VOC contents of 2K-PU coatings obtained from MHPs were low to 300 g/L. |
Note de contenu : |
- EXPERIMENTAL : Materials and reagents - Instruments and measurements - Synthesis of multiarm star hydroxyl-terminated polyesters - Preparation of varnishes and test of film properties
- RESULTS AND DISCUSSION : Influence of monocarboxylic acids - Structural characterization of MHPs - Dilution curves and intrinsic viscosities of MHPs - Thermal stability of cured films - Film properties of MHPs |
DOI : |
10.1007/s11998-016-9883-4 |
En ligne : |
https://link.springer.com/content/pdf/10.1007%2Fs11998-016-9883-4.pdf |
Format de la ressource électronique : |
Pdf |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=28561 |
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 14, N° 3 (05/2017) . - p. 505-516