Anti-corrosion coatings loaded with mesostructured particles
Coatings, for example polymer coatings or sol-gel coatings, including at least one layer of micrometric, individualised and mesostructured spherical particles. The particles having been created and loaded with at least one element selected from corrosion-inhibiting functional molecules and corrosion-inhibiting functional nano-objects, by a method having non-dissociable nebulization-heating steps that are continuous in a single reactor. The coatings form an anti-corrosion system, having mechanical strength and/or for coloring. The coatings are applicable, in particular, in the field of protecting light aeronautical alloys against corrosion.
1. A coating comprising at least one layer comprising individual and mesostructured spherical micrometric particles, said mesostructured spherical micrometric particles being loaded with at least one element selected from among functional corrosion-inhibiting molecules and functional corrosion-inhibiting nano-objects and formed by a continuous non-dissociable nebulization of a liquid solution at a predetermined molar concentration in a solvent to obtain a fog of solution droplets and heating the fog solution droplets to evaporate the solvent and volatile compounds in a single reactor, the liquid solution comprising one or more precursors from a three-dimensional network of particles and said at least one element chosen from the functional corrosion-inhibiting molecules and the functional corrosion-inhibiting nano-objects; and wherein said at least one layer is a sealed hybrid organic-inorganic layer, containing a sol-gel or sealed primer layer, that is closed and sealed to limit penetration of corrosive materials.
2. The coating as claimed in claim 1 , wherein said at least one layer is a mesostructured matrix comprising said at least one element selected from among the functional corrosion-inhibiting molecules and the functional corrosion-inhibiting nano-objects.
3. The coating as claimed in claim 2 , wherein the mesostructured matrix is obtained from a suspension comprising at least one element selected from an inorganic precursor and a hybrid organic-inorganic precursor, in macromolecular form.
4. The coating as claimed in claim 2 , further comprising a sealed upper hybrid organic-inorganic layer comprising sol-gel or an upper sealed primer layer.
5. The coating as claimed in claim 2 , wherein the mesostructured matrix comprises functional organosilanes bearing at least one group selected from an amino group, a sulfide, a carboxyl and a thiol.
6. The coating as claimed in claim 1 , wherein the mesostructured spherical micrometric particles incorporated in the coating have a diameter between 0.1 and 10 micrometers.
7. The coating as claimed in claim 1 , wherein the mesostructured spherical micrometric particles incorporated in the coating have a sphericity coefficient greater than or equal to 0.75.
8. The coating as claimed in claim 1 , wherein the mesostructured spherical micrometric particles incorporated in the coating present a mesostructure with segregation of organic and inorganic or hybrid organic-inorganic phases periodically organized with a periodicity, between the two phases, between 2 and 50 nanometers.
9. The coating as claimed in claim 8 , wherein the periodicity between the two phases is between 2 and 15 nanometers.
10. The coating as claimed claim 1 is applied to protect light alloys in aeronautic and aerospace fields.
11. An aircraft comprising a coating as claimed in claim 1 .
12. The coating as claimed in 1 , wherein an inorganic portion of the sealed hybrid organic-inorganic layer provides scratch resistance to the coating and an organic portion of the sealed hybrid organic-inorganic layer increases flexibility of the coating.