Patent ID: 7585926

Claim:
A curable fluorine-containing polymer having a hydrolyzable metal alkoxide moiety which has a number average molecular weight of from 500 to 1,000,000 and is represented by the formula (2): M N A (2) wherein the structural unit M is a structural unit derived from a fluorine-containing ethylenic monomer having a hydrolyzable metal alkoxide moiety and represented by the formula (M): in which X 1 and X 2 are the same or different, and each is H or F; X 3 is H, F, CH 3 or CF 3 ; X 4 and X 5 are the same or different, and each is H, F or CF 3 ; Rf 1 is represented by the formula: —D—Ry wherein —D— is a fluoroether unit represented by the formula (D): O—R n or R—O n (D) in which n is an integer of 1 to 20; R is at least one selected from fluorine-containing divalent alkylene groups having 1 to 5 carbon atoms where at least one of hydrogen atoms is replaced by fluorine atom, and R may be the same or different when n is not less than two; Ry is a hydrocarbon group having 1 to 39 carbon atoms where a part or the whole of hydrogen atoms are replaced by fluorine atoms or a hydrocarbon group having 1 to 99 carbon atoms and ether bond where a part or the whole of hydrogen atoms are replaced by fluorine atoms, which is an organic group in which one to three of hydrogen atoms are replaced by Y 1 where Y 1 is a functional group having, at its end, at least one hydrolyzable metal alkoxide moiety having 1 to 50 carbon atoms; a is 0 or an integer of 1 to 3; b and c are the same or different, and each is 0 or 1, the structural unit N is a structural unit derived from a fluorine-containing ethylenic monomer and represented by the formula (N): in which X 1 and X 2 are the same or different, and each is H or F; X 3 is H, F, CH 3 or CF 3 ; X 4 and X 5 are the same or different, and each is H, F or CF 3 ; Rf 2 is a fluorine-containing alkyl group having 1 to 40 carbon atoms or a fluorine-containing alkyl group having 2 to 100 carbon atoms and ether bond, which is an organic group in which 1 to 3 hydrogen atoms are replaced by Y 2 where Y 2 is a monovalent organic group having 2 to 10 carbon atoms and having, at its end, an ethylenic carbon-carbon double bond; a is 0 or an integer of 1 to 3; b and c are the same or different, and each is 0 or 1, the structural unit A is a structural unit derived from a monomer being copolymerizable with the fluorine-containing ethylenic monomers providing the structural units represented by the formulae (M) and (N), and the structural units M, N and A are contained in amounts of from 0.1 to 100% by mole, from 0 to 99.9% by mole and from 0 to 99.9% by mole, respectively.