Fluorochemical urethane-silane compounds and aqueous compositions thereof
Fluorochemical urethane compounds and coating compositions derived therefrom are described. The compounds and composition may be used in treating substrates, in particular substrates having a hard surfaces such as ceramics or glass, to render them hydrophilic, oleophobic and easy to clean.
1. A compound of the formula
wherein R f is
R f 1 is a monovalent perfluoroalkyl or a perfluorooxyalkyl group, or a divalent perfluoroalkylene or a perfluorooxyalkylene group,
Q is a covalent bond, or a polyvalent alkylene group of valency z,
X is —O—, —NR 4 — or S—, where R 4 is H or C 1 -C 4 alkyl,
y is 1 or 2, and
z is independently 1 or 2,
R 1 is the residue of a polyisocyanate selected from multivalent aliphatic, alicyclic, or aromatic moiety,
W is
where W 1 is a water-solubilizing group selected from carboxylate, sulfate, sulfonate, phosphate, phosphonate, ammonium, quaternary ammonium, poly(oxyalkylene), and mixtures thereof,
X 4 is —O—, —NR 4 — or —S—, where R 4 is H or C 1 -C 4 alkyl;
and v is 1 or 2;
R 2 is of the formula:
Y is a hydrolysable group selected from a halide, a C 1 -C 4 alkoxy group, an acyloxy group or a polyoxyalkylene group,
R 6 is a monovalent alkyl or aryl group,
p is 1, 2 or 3, and
q is 1 to 5;
each R 5 is a divalent alkylene group, said alkylene groups optionally containing one or more catenary oxygen atoms;
each X 1 is —O— or —NR 4 —, where R 4 is H or C 1 -C 4 alkyl,
each R 3 is a polyvalent alkylene or arylene groups, or combinations thereof, said alkylene groups optionally containing one or more catenary oxygen atoms;
x and y are each independently at least 1, and z is independently 1 or 2.
2. The compounds of claim 1 wherein R f 1 comprises a perfluorooxyalkylene group comprising perfluorinated repeating units selected from the group consisting of
—(C n F 2n O)—, —(CF(Z)O)—, —(CF(Z)C n F 2n O)—, —(C n F 2n CF(Z)O)—, —(CF 2 CF(Z)O)—, and combinations thereof, wherein n is 1 to 4 and Z is a perfluoroalkyl group, a perfluoroalkoxy group, or perfluoroether group.
3. The compounds of 1 wherein R f 1 comprises a group of the formula R f 6 —R f 3 —O—O—R f 4 —(R f 5 ) q .
wherein
R f 6 is F for monovalent perfluorooxyalkyl, and an open valence (“−”) for divalent perfluorooxyalkylene;
R f 3 represents a perfluoroalkylene group,
R f 4 represents a perfluoroalkyleneoxy group consisting of periluoroalkyleneoxy groups having 1, 2, 3 or 4 carbon atoms or a mixture of such periluoroalkyleneoxy groups,
R f 5 represents a perfluoroalkylene group, and
q is 0 or 1.
4. The compound of claim 1 wherein said periluorooxyalkylene group is selected from one or more of [CF 2 CF 2 O] r ; —[CF(CF 3 )—CF 2 —O] s —; [CF 2 CF 2 O] r —[CF 2 O] t , —[CF 2 CF 2 CF 2 CF 2 —O] u and [CF 2 CF 2 O] r [CF(CF 3 )CF 2 O] s ; wherein each of r, s, t and u each are integers of 1 to 50.
5. The compounds of claim 1 wherein R f is a monovalent perfluorooxyalikylene group and z is 1.
6. The compounds of claim 1 wherein the molar ratio of silane groups to —NH—C(O)—X 1 — groups is greater than 1:1.
7. The compounds of claim 1 wherein R f is derived from a fluorinated polyol.
8. The compounds of claim 1 , derived from the free-radical addition of a thiosilane to an ethylenically unsaturated group.
9. The compounds of claim 1 , wherein Y is a halogen, a C 1 -C 4 alkoxy group, or a C 1 -C 4 acyloxy group.
10. The compounds of claim 1 wherein the water solubilizing group W 1 is represented by —CO 2 M, —OH, —OSO 3 M, —SO 3 M, —PO(OM) 2 , —P(OM) 3 , and —N(R 8 ) 3 X, wherein each R 8 is selected from the group consisting of a phenyl group, a cycloaliphatic group, or an aliphatic group having from about 1 to 12 carbon atoms, M is H or one equivalent of a monovalent or divalent soluble cation selected from sodium, potassium, calcium, and N(R 4 ) 3 H+, R 4 is H or C 1 -C 4 alkyl, and X is a soluble anion.
11. A coating composition comprising at least one compound of claim 1 and a solvent.
12. The composition of claim 11 further comprising an aminosilane.
13. A coating composition comprising an aqueous dispersion or suspension of the compounds of claim 1 .
14. The coating composition of claim 11 , further comprising an silsequioxane.
15. A compound of claim 1 comprising the free radical reaction product of a thiosilane with a fluorochemical urethane compound having pendent ethylenically unsaturated groups, said fluorochemical urethane compound comprising the reaction product of a polyisocyanate, a nucleophilic fluorinated compound, a nucleophilic water-solubilizing compound and a nucleophilic ethylenically unsaturated compound.
16. A method of preparing the compound of claim 1 comprising the step of free radical addition of a thiosilane to a urethane compound of the formula:
wherein
R f is a perfluorinated group,
R 1 is the residue of a polyisocyanate,
X 1 is —O— or —NR 4 —, where R 4 is H or C 1 -C 4 alkyl,
R 3 is a divalent alkylene or arylene groups, or combinations thereof, said alkylene groups optionally containing one or more catenary oxygen atoms;
z is independently 1 or 2,
x is 1 or 2; and
q is 1 to 5.
17. The method of claim 16 wherein the thiosilane is of the formula
wherein
R 5 is a divalent alkylene group, said alkylene groups optionally containing one or more catenary oxygen atoms;
Y is a hydrolysable group,
R 6 is a monovalent alkyl or aryl group, and
p is 1, 2 or 3.
18. The method of claims 16 wherein the moiety —R 3 —(CH═CH 2 ) comprises a vinyl group, an allyl group or an allyloxy group.
19. A method of preparing the compound of claim 1 comprising the step of free radical addition of a water-solubilizing compound of the formula HS—R 5 —W 1 , wherein R 5 is a divalent alkylene group, said alkylene groups optionally containing one or more catenary oxygen atoms, and W 1 is a water-solubilizing group;
to a urethane compound of the formula:
wherein
R f is a perfluorinated group,
R f is the residue of a polyisocyanate,
X 1 is —O— or —NR 4 —, where R 4 is H or C 1 -C 4 alkyl,
R 3 is a divalent alkylene or arylene groups, or combinations thereof, said alkylene groups optionally containing one or more catenary oxygen atoms;
z is independently 1 or 2, and
q is 1 to 5.
20. A method of preparing the compound of claim 1 comprising the step of free radical addition of a water-solubilizing compound of the formula HS—R 5 —W 1 , wherein R 5 is a divalent alkylene group, said alkylene groups optionally containing one or more catenary oxygen atoms, and W 1 is a water-solubilizing group; and free-radical addition of a thiosilane,
to a urethane compound of the formula:
wherein
R f is a perfluorinated group,
R 1 is the residue of a polyisocyanate,
X 1 is —O— or —NR 4 —, where R 4 is H or C 1 -C 4 alkyl,
R 3 is a divalent alkylene or arylene groups, or combinations thereof, said alkylene groups optionally containing one or more catenary oxygen atoms;
z is independently 1 or 2, and
q is 1 to 5.