Claims
- 1. A thermodynamically stable microemulsion of the oil-in-water (o/w) or water in oil (w/o) type, consisting of the following components:
- water,
- a liquid perfluoropolyether substantially insoluble in water having an average molecular weight of from 1,500 to 10,000 and end groups at least partially of the functionalized hydrophylic type,
- an ionic or non-ionic perfluorinated surfactant in an amount from 0 to 21 weight percent,
- a co-surfactant, consisting of a hydrogenated alcohol having 1 to 12 carbon atoms, and
- optionally one or more water-soluble electrolytes, said functionalized end groups being represented by the formula
- --(B).sub.n T.sub.m
- wherein n=0 or 1,
- B is a linking hydrocarbon radical, either divalent or polyvalent, in particular an alkylene or a cycloalkylene or an arylene radical, having up to 20 carbon atoms,
- m varies from 1 to 3, and
- T is one of the following groups or radicals:
- --COOH, --SO.sub.3 H, --OH, polyoxyalkylene--OH, an ester or amidic or aminic or quaternary ammonium group with the proviso that when n=0, T also includes H,
- whereby the microemulsions exhibit the property of requiring, for being formed, a lower surfactant amount with respect to corresponding microemulsions of perfluoropolyethers having perfluoroalkyl end groups;
- wherein the perfluoropolyether consists of fluorooxyalkylene units selected from the group consisting of: ##STR5## and in particular belonging to the following groups: ##STR6## with a random distribution of the perfluorooxyalkylene units, where m, n, p have such average values as to meet the abovesaid requirements regarding the previously indicated molecular weight and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- (2) R.sub.f O(CF.sub.2 CF.sub.2 O).sub.n (CF.sub.2 O).sub.m R'.sub.f
- with a random distribution of the perfluorooxyalkylene units, wherein m, n have such values as to meet the abovesaid requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups; ##STR7## wherein m, n, p, o have such values as to meet the above-indicated requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups; ##STR8## wherein n has such a value as to meet the above-indicated requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- (5) R.sub.f O(CF.sub.2 CF.sub.2 O).sub.n R'.sub.f
- wherein n has such an average value as to meet the abovesaid requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- (6) R.sub.f O(CF.sub.2 CF.sub.2 CF.sub.2 O).sub.n R'.sub.f or R.sub.f O(CH.sub.2 CF.sub.2 CF.sub.2 O).sub.n R'.sub.f
- wherein n has such a value as to meet the abovesaid requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups.
- wherein said thermodynamically stable microemulsion is spontaneously formed by simple mixing of the components.
- 2. Microemulsions according to claim 1 wherein the perfluoropolyether of classes 1, 2 and 3 are rough products of the photo-oxidation process containing peroxide groups --OO-- in the chain.
- 3. A thermodynamically stable microemulsion according to claim 1, wherein the functionality is between 0.3 and 1.
- 4. The thermodynamically stable microemulsion according to claim 1, wherein the functionality is between 0.1 and 4.
- 5. The thermodynamically stable microemulsion according to claim 1, wherein the molecular weight is between 2,000 and 6,000.
- 6. The microemulsion of claim 1, wherein the perfluorinated surfactant is selected from the group consisting of:
- (a) C.sub.5 -C.sub.11 perfluorocarboxylic acids and the salts thereof;
- (b) C.sub.5 -C.sub.11 perfluorosulphonic acids and the salts thereof;
- (c) non-ionic surfactants consisting of a perfluoroalkyl chain and of a polyoxyalkylene hydrophilic head;
- (d) mono- and bi-carboxylic acids derived from perfluoropolyethers having a mean molecular weight not higher than 1,000, and the salts thereof;
- (e) non-ionic surfactants consisting of a perfluoropolyether chain bound to a polyoxyalkylene chain; and,
- (f) perfluorinated cationic surfactants or those derived from perfluoropolyethers having 1, 2 or 3 hydrophobic chains.
- 7. The microemulsion of claim 1, wherein T is a --COOH, an --OH, a polyoxyalkylene--OH, or a quaternary ammonium group.
- 8. A thermodynamically stable microemulsion of the oil-in-water (o/w) or water in oil (w/o) type form, in the absence of a fluorinated surfactant, consisting of the following components: water, an ionic or non-ionic liquid perfluoropolyether substantially insoluble in water in an amount from 0 to 21 weight percent and having an average molecular weight of from 1,500 to 10,000 and end groups at least partially of the functionalized hydrophylic type, and optionally one or more water-soluble electrolytes, said functionalized end groups being represented by the formula
- --(B).sub.n T.sub.m
- wherein n=0 or 1, B is a linking hydrocarbon radical, either divalent or polyvalent, in particular an alkylene or a cycloalkylene or an arylene radical, having up to 20 carbon atoms, m varies from 1 to 3, and T is one of the following groups or radicals: --COOH, --SO.sub.3 H, --OH, polyoxyalkylene--OH, an ester or amidic or aminic or quaternary ammonium group, with the proviso that when n=0, T also includes H;
- wherein the perfluoropolyether consists of fluorooxyalkylene units selected from the group consisting of: ##STR9## and in particular belonging to the following groups: ##STR10## with a random distribution of the perfluorooxyalkylene units, where m, n, p have such average values as to meet the abovesaid requirements regarding the previously indicated molecular weight and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- (2) R.sub.f O(CF.sub.2 CF.sub.2 O).sub.n (CF.sub.2 O).sub.m R'.sub.f
- with a random distribution of the perfluorooxyalkylene units, wherein m, n have such values as to meet the abovesaid requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups; ##STR11## wherein m, n, p, o have such values as to meet the above-indicated requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups; ##STR12## wherein n has such a value as to meet the above-indicated requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- (5) R.sub.f O(CF.sub.2 CF.sub.2 O).sub.n R'.sub.f
- wherein n has such an average value as to meet the abovesaid requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- (6) R.sub.f O(CF.sub.2 CF.sub.2 CF.sub.2 O).sub.n R'.sub.f or R.sub.f O(CH.sub.2 CF.sub.2 CF.sub.2 O).sub.n R'.sub.f
- wherein n has such a value as to meet the abovesaid requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- wherein said thermodynamically stable microemulsion is spontaneously formed by simple mixing of the components.
- 9. A thermodynamically stable microemulsion of the oil-in-water (o/w) or water in oil (w/o) type, comprising the following components: water, a rough perfluoropolyether substantially insoluble in water having an average molecular weight of from 1,500 to 10,000 and end groups at least partially of the functionalized hydrophylic type, perfluorinated surfactant in an amount of from 0 to 21 weight present, a co-surfactant which is hydrogenated, wherein said at least partially functionalized end groups are represented by the formula
- --(B).sub.n T.sub.m
- wherein n=0 or 1, B is a linking hydrocarbon radical, either divalent or polyvalent, in particular an alkylene or cycloalkylene or an arylene radical, having up to 20 carbon atoms, m varies from 1 to 3, and T is one of the following groups or radicals: --COOH, --SO.sub.3 H, --OH, polyoxyalkylen--OH, an ester or amidic or aminic or quaternary ammonium group, with the proviso that when n=0, T also includes H;
- wherein the perfluoropolyether consists of fluorooxyalkylene units selected from the group consisting of: ##STR13## and in particular belonging to the following groups: ##STR14## with a random distribution of the perfluorooxyalkylene units, where m, n, p have such average values as to meet the abovesaid requirements regarding the previously indicated molecular weight and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- (2) R.sub.f O(CF.sub.2 CF.sub.2 O).sub.n (CF.sub.2 O).sub.m R'.sub.f
- with a random distribution of the perfluorooxyalkylene units, wherein m, n have such values as to meet the abovesaid requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups; ##STR15## wherein m, n, p, o have such values as to meet the above-indicated requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups; ##STR16## wherein n has such a value as to meet the above-indicated requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- (5) R.sub.f O(CF.sub.2 CF.sub.2 O).sub.n R'.sub.f
- wherein n has such an average value as to meet the abovesaid requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- (6) R.sub.f O(CF.sub.2 CF.sub.2 CF.sub.2 O).sub.n R'.sub.f or R.sub.f O(CH.sub.2 CF.sub.2 CF.sub.2 O).sub.n R'.sub.f
- wherein n has such a value as to meet the abovesaid requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- wherein said thermodynamically stable microemulsion is spontaneously formed by simple mixing of the components.
- 10. The microemulsion of claim 9 further comprising absence of said perfluorinated surfactant.
- 11. The microemulsion of claim 10 wherein the co-surfactant is an alcohol.
- 12. The microemulsion of claim 11 wherein the alcohol is t-butanol.
- 13. The microemulsion of claim 12 wherein the water is present in an amount ranging from about 1.5 to about 16% by weight, wherein the perfluoropolyether is present in an amount ranging from about 72 to about 84% by weight, and wherein the t-butanol is present in an amount ranging from about 13 to about 15% by weight.
- 14. A microemulsion consisting essentially of the following components: water, an alcohol and a rough perfluoropolyether substantially insoluble in water having a molecular weight of from 2,000 to 6,000 and having end groups comprising --H, --COOH, --SO.sub.3 H, --OH, polyoxyalkylene--OH, an ester or amidic or aminic or quaternary ammonium group;
- wherein the perfluoropolyether consists of fluorooxyalkylene units selected from the group consisting of: ##STR17## and in particular belonging to the following groups: ##STR18## with a random distribution of the perfluorooxyalkylene units, where m, n, p have such average values as to meet the abovesaid requirements regarding the previously indicated molecular weight and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- (2) R.sub.f O(CF.sub.2 CF.sub.2 O).sub.n (CF.sub.2 O).sub.m R'.sub.f
- with a random distribution of the perfluorooxyalkylene units, wherein m, n have such values as to meet the abovesaid requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups; ##STR19## wherein m, n, p, o have such values as to meet the above-indicated requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups; ##STR20## wherein n has such a value as to meet the above-indicated requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- (5) R.sub.f O(CF.sub.2 CF.sub.2 O).sub.n R'.sub.f
- wherein n has such an average value as to meet the abovesaid requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- (6) R.sub.f O(CF.sub.2 CF.sub.2 CF.sub.2 O).sub.n R'.sub.f or R.sub.f O(CH.sub.2 CF.sub.2 CF.sub.2 O).sub.n R'.sub.f
- wherein n has such a value as to meet the abovesaid requirements and Rf and R'f are the above defined functional groups and, optionally, in part perfluoroalkyl groups;
- wherein said thermodynamically stable microemulsion is spontaneously formed by simple mixing of the components.
- 15. The microemulsion of claim 14 wherein the water is about 1.5 to about 16% by weight of the microemulsion, wherein the perfluoropolyether is about 72 to 84% by weight of the microemulsion, and wherein the alcohol is t-butanol and is about 13 to 15% by weight of the microemulsion.
Priority Claims (1)
| Number |
Date |
Country |
Kind |
| 22420/87 |
Oct 1987 |
ITX |
|
Parent Case Info
This is a continuation of application Ser. No. 07/841,291, filed on Feb. 28, 1992, now abandoned, which is a continuation of Ser. No. 07/563,841 filed on Aug. 7, 1990, now abandoned, which is a continuation of Ser. No. 07/261,226 filed on Oct. 24, 1988, now abandoned.
US Referenced Citations (13)
Foreign Referenced Citations (2)
| Number |
Date |
Country |
| 227103 |
Jul 1987 |
EPX |
| 250766 |
Jan 1988 |
EPX |
Non-Patent Literature Citations (1)
| Entry |
| "Microemulsions Theory and Practice", Leon M. Prince, Academic Press Rapid Manuscript, 1977. |
Continuations (3)
|
Number |
Date |
Country |
| Parent |
841291 |
Feb 1992 |
|
| Parent |
563841 |
Aug 1990 |
|
| Parent |
261226 |
Oct 1988 |
|
Patent Grant
5656201
