| Titre : |
Nano-silica-containing acrylic polyurethane and acrylic-polyester hybrid polyurethane coatings for direct-to-metal (DTM) coating applications – a comparative study |
| Type de document : |
texte imprimé |
| Auteurs : |
Sukanya Gangopadhyay, Auteur ; Prakash A. Mahanwar, Auteur |
| Année de publication : |
2022 |
| Article en page(s) : |
p. 1773-1786 |
| Note générale : |
Bibliogr. |
| Langues : |
Américain (ame) |
| Catégories : |
Anticorrosion
Application directe sur le métal
Chimie analytique
Copolymère ester acrylique
Copolymère uréthane acrylique
Formulation (Génie chimique)
Matériaux hybrides
Nanoparticules
Résistance aux conditions climatiques
Résistance chimique
Revêtements -- Propriétés mécaniques
Revêtements -- Propriétés optiques
Revêtements organiques
SiliceLa silice est la forme naturelle du dioxyde de silicium (SiO2) qui entre dans la composition de nombreux minéraux.
La silice existe à l'état libre sous différentes formes cristallines ou amorphes et à l'état combiné dans les silicates, les groupes SiO2 étant alors liés à d'autres atomes (Al : Aluminium, Fe : Fer, Mg : Magnésium, Ca : Calcium, Na : Sodium, K : Potassium...).
Les silicates sont les constituants principaux du manteau et de l'écorce terrestre. La silice libre est également très abondante dans la nature, sous forme de quartz, de calcédoine et de terre de diatomée. La silice représente 60,6 % de la masse de la croûte terrestre continentale.
|
| Index. décimale : |
667.9 Revêtements et enduits |
| Résumé : |
In the era of sustainability, direct-to-metal coatings have proven to be a promising solution as it eliminates the need for underneath primer coating layers. In the present study, two coating systems, viz. acrylic polyurethane and acrylic-polyester hybrid polyurethane nano-composite coatings, were prepared by addition of nano-silica in various loadings for direct-to-metal coating applications. The addition of nano-silica along with selected resin systems enables to meet desired mechanical properties, chemical resistance along with weathering and corrosion resistance of DTM coating system. Incredible improvement in the overall mechanical properties of the coating including pencil hardness and scratch resistance has been observed by the addition of nano-silica. SEM technique was employed to evaluate the nano-silica dispersion into the coating system along with its morphology. SEM studies revealed thorough dispersion of the nanoparticles within the coating matrix for both the coating systems. Thermal properties were studied by thermogravimetric analysis along with structural characterization by Fourier transform infrared spectroscopy. Thermal stability of both the coating systems increased with the addition of nano-silica; however, acrylic-polyester hybrid polyurethane coatings revealed better thermal stability at 8% nano-silica loading. Color and gloss changes were studied before and after 500 h exposure to a QUV chamber. Anticorrosive properties were evaluated by salt spray exposure for 700 h. At 8% nano-silica loading, acrylic-polyester hybrid polyurethane coatings revealed better weathering performance along with anticorrosive properties and chemical resistance owing to the presence of hybrid polymer chains. |
| Note de contenu : |
- EXPERIMENTAL : Materials - Preparation of nano-composite DTM coating - polyurethane (PPT) nano-composite DTM coating - Application - Coating characterization
- RESULTS AND DISCUSSION : Fourier transfer infrared spectroscopy (FTIR) analysis - Mechanical properties of coating formulations -
Scanning electron microscopy (SEM) - Thermogravimetric analysis (TGA) of coatings - Chemical resistance of APT and PPT coatings -
Optical properties - Corrosion and weathering resistance
- Table 1 : Formulations of acrylic polyurethane (APT) nano-composite DTM coating
- Table 2 : Formulations of acrylic-polyester hybrid
- Table 3 : Mechanical properties of APT and PPT coatings at various nano-silica loadings
- Table 4 : TGA of acrylic polyurethane (APT) DTM coating
- Table 5 : TGA of acrylic-polyester hybrid polyurethane (PPT) DTM coating
- Table 6 : Chemical resistance properties of APT and PPT coating systems at various nano-silica loading
- Table 7 : Gloss reading at 60° inclination for APT and PPT coating systems at various nano-silica loading
- Table 8 : Gloss measured 60° inclination before and after weathering test at various nano-silica loadings for APT and PPT coatings
- Table 9 : Color changes (ΔE values) of specimens (APT and PPT coatings) before and after the QUV chamber exposure test |
| DOI : |
https://doi.org/10.1007/s11998-022-00647-5 |
| En ligne : |
https://link.springer.com/content/pdf/10.1007/s11998-022-00647-5.pdf?pdf=button% [...] |
| Format de la ressource électronique : |
Pdf |
| Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38496 |
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 19, N° 6 (11/2022) . - p. 1773-1786
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Nano-silica-containing acrylic polyurethane and acrylic-polyester hybrid polyurethane coatings for direct-to-metal (DTM) coating applications – a comparative study in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 19, N° 6 (11/2022)
