| Titre : |
Preparation of tough silicon-oxo coatings with enhanced hardness from moisture-curable polysiloxane and silica alcosol |
| Type de document : |
texte imprimé |
| Auteurs : |
Ting He, Auteur ; Shuxue Zhou, Auteur |
| Année de publication : |
2015 |
| Article en page(s) : |
p. 767-776 |
| Note générale : |
Bibliogr. |
| Langues : |
Américain (ame) |
| Catégories : |
Gel de silice
Matériaux hybrides
Revêtements -- Propriétés mécaniques
SiliconesLes silicones, ou polysiloxanes, sont des composés inorganiques formés d'une chaine silicium-oxygène (...-Si-O-Si-O-Si-O-...) sur laquelle des groupes se fixent, sur les atomes de silicium. Certains groupes organiques peuvent être utilisés pour relier entre elles plusieurs de ces chaines (...-Si-O-...). Le type le plus courant est le poly(diméthylsiloxane) linéaire ou PDMS. Le second groupe en importance de matériaux en silicone est celui des résines de silicone, formées par des oligosiloxanes ramifiés ou en forme de cage (wiki).
Sol-gel, Procédé
|
| Index. décimale : |
667.9 Revêtements et enduits |
| Résumé : |
Hardness and toughness are typically contradictive for sol–gel-derived coatings. In this article, thick (~15 μm) silicon-oxo-dominated nanocomposite coatings with high transparency were fabricated by incorporating 3-methacryloxypropyltrimethoxysilane (MPS)-modified silica alcosol into a moisture-curable polysiloxane oligomer and curing with the aid of 3-aminopropyltriehtoxysilane (APS). Effects of MPS-to-SiO2 molar ratio, SiO2 nanoparticle content, APS dosage, and curing process on the mechanical properties were thoroughly investigated using a pencil hardness tester, a flexibility tester, and a nanoindentation tester. The best properties were achieved by a coating with an MPS-to-SiO2 molar ratio of 0.1:1, a silica nanoparticle content of 10 wt%, and an APS dosage of 30 wt%. This coating demonstrated enhanced hardness (pencil hardness = 7H and microhardness = 626 MPa) and toughness (excellent flexibility of 5 mm in the mandrel bend test). Additional curing via aza-Michael addition between amino groups from APS and C=C groups from the polysiloxane oligomer can be accomplished at elevated temperatures. This enables further mechanical enhancement, namely hardness (9H and 1087 MPa), with adequate flexibility (10 mm). Such properties are superior to those reported for other sol–gel-derived silicon-oxo coatings produced at low drying temperatures. |
| Note de contenu : |
- EXPERIMENTAL : Materials - Synthesis of polysiloxane oligomer - Preparation of MPS-functionalized colloidal silica - Fabrication of silicon-oxo-dominated coatings - Characterization
- RESULTS AND DISCUSSION : Preparation of silicon-oxo-dominated nanocomposites coatings - The macro-mechanical properties of the silicon-oxo coatings - Micromechanical properties of silicon-oxo coatings - Effect of the curing process on mechanical properties |
| DOI : |
10.1007/s11998-015-9676-1 |
| En ligne : |
https://link.springer.com/content/pdf/10.1007%2Fs11998-015-9676-1.pdf |
| Format de la ressource électronique : |
Pdf |
| Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=24411 |
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 12, N° 4 (07/2015) . - p. 767-776
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Preparation of tough silicon-oxo coatings with enhanced hardness from moisture-curable polysiloxane and silica alcosol in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 12, N° 4 (07/2015)
