Method for making a nanofiltration membrane, and resulting membrane
OwnerJean-Christophe Remigy, Philippe Aptel +2inventors
InventorsJean-Christophe Remigy, Philippe Aptel, Sandrine Desclaux, Alain Ricard
Life of this patent
Estimating the term…
Abstract
The invention concerns a method for producing a nanofiltration membrane. At least one face (30) of a porous membrane (3) is put in the presence of a grafting composition comprising at least one monomer grafted by radical polymerisation and at least one crosslinking agent, that is however free from photoinitiator, and of light radiation capable of forming free radicals during a predetermined period adapted so as to obtain nanofiltration properties. The invention also extends to the nanofiltration membrane obtained in this way of which the properties may be precisely predetermined and which resist ageing.
Claims26
A method for preparing a nanofiltration membrane, wherein:
- the starting point is a porous membrane (3,9), a so-called supporting membrane, having at least one face, a so-called grafting face (12,30), having filtration properties in the range defined by microfiltration or ultrafiltration and, at least on this grafting face, at least one agent, a so-called photosensitive agent, capable of generating free radicals when it is subjected to light radiation,
- the grafting face (12,30) is put in the presence of:
- a grafting composition containing at least one monomer, a so-called grafting monomer, capable of forming at least one polymer by radical polymerisation, and at least one crosslinking agent adapted so as to bring about crosslinking of at least one polymer formed by radical polymerisation, the molar quantity of crosslinking agent(s) being less than that of the grafting monomer(s) in the composition, this grafting composition being free from a photoinitiating agent,
- light radiation capable of activating the formation of free radicals by the photosensitive agent of the supporting membrane (3,9) in the absence of a photoinitiating agent in the grafting composition, during a predetermined period, adapted as a function of the characteristics of the light radiation so as to obtain the nanofiltration properties of the membrane.
A nanofiltration membrane wherein it comprises:
- a porous membrane (3,9), a so-called supporting membrane, having at least one face, a so-called grafting face (12,30) having filtration properties in the range defined by microfiltration and ultrafiltration,
- a graft of at least one crosslinked polymer grafted onto the grafting face, this graft being adapted so as to confer nanofiltration properties on the grafting face.
Dependencies are inferred from the claim text.