Claims
- 1. An article comprising a marine structure coated with an anti-fouling coating which is the addition cured reaction product of a composition comprising:
- (A) at least one polyorganosiloxane comprising, per molecule, an average of at least two organic radicals bound to silicon which have therein a carbon-carbon double bond;
- (B) at least one polyorganosiloxane comprising an average of at least two Si--H moieties per molecule, in an amount such that the ratio of equivalents of component B to component A is in the range of about 1.1-1.6:1;
- (C) about 15-30 parts by weight, per 100 parts of component A, of suspended silica having a surface area in the range of about 100-600 m.sup.2 /g;
- (D) a catalytically effective proportion of a platinum group hydrosilylation catalyst; and
- (E) an amount effective to provide storage stability of at least one polymerization inhibitor;
- with the proviso that either component A or component B comprises at least one internally functional polyorganosiloxane containing functional groups which incorporate internal silicon atoms, the ratio of equivalents of said internally functional polyorganosiloxane to total polyorganosiloxanes in said component A or component B being in the range of about 0.3-0.7:1; the other of component A or component B comprising only terminally functional polyorganosiloxanes.
- 2. An article according to claim 1 wherein the marine structure is a ship's hull.
- 3. An article according to claim 1 which comprises a layer of a primer composition on said surface, followed by said anti-fouling coating.
- 4. An article according to claim 1 wherein said marine structure is of iron, aluminum or a fiber-reinforced thermoplastic or thermoset resin.
- 5. An article according to claim 4 wherein component A has the formula ##STR3## and component B has the formula ##STR4## wherein each R.sup.1 is independently a hydrocarbon or fluorinated hydrocarbon radical, at least two R.sup.1 radicals per molecule having therein a carbon-carbon double bond; each R.sup.2 is independently a hydrocarbon or fluorinated hydrocarbon radical, at least two R.sup.2 radicals per molecule being hydrogen; and each of m and n has an average value in the range of about 10-1,000.
- 6. An article according to claim 5 wherein component A is a vinyl-substituted polydimethylsiloxane and component B is a polydimethylsiloxane containing Si--H moieties.
- 7. An article according to claim 6 wherein the ratio of equivalents of internally functional polyorganosiloxane to total polyorganosiloxane in component A or B is in the range of about 0.3-0.7:1.
- 8. An article according to claim 6 wherein component B comprises internally and terminally functional polydimethylsiloxanes.
- 9. An article according to claim 5 wherein component C is fumed silica.
- 10. An article according to claim 5 wherein component D is a platinum-containing catalyst.
- 11. An article according to claim 5 wherein component E is an acetylenic alcohol, vinyl-substituted cyclic polyorganosiloxane or stable free radical.
Government Interests
This invention was made with government support under Contract No. N61533-93-C-0062 awarded by the Department of the Navy. The government has certain rights in this invention.
US Referenced Citations (6)
Foreign Referenced Citations (2)
Number |
Date |
Country |
320716A2 |
Jun 1989 |
EPX |
646672A1 |
Apr 1995 |
EPX |