Claims
- 1. A fluorosilicone composition cured in the presence of a free radical generating cross-linking initiator or catalyst and diluent to form a pressure sensitive adhesive having high solvent resistance comprising by weight:
- (A) about 5 to 70 percent fluorosilicone polymers;
- (B) about 10 to 60 percent of a silanol containing MQ resin; and
- (C) about 10 to 50 percent of resin compatible diorganosiloxane polymers having (SiR.sup.1 R.sup.2 O) repeating units where R.sup.1 and R.sup.2 are independently selected from alkyl groups having 1 to about 10 carbon atoms, alkenyl groups having 1 to about 10 carbon atoms or an aryl group, Components (A), (B) and (C) substantially equaling 100 weight percent solids.
- 2. The fluorosilicone composition of claim 1, wherein Component (A) is present in an amount ranging from about 20 to about 60 weight percent.
- 3. The fluorosilicone composition of claim 1, wherein Component (A) is present in an amount ranging from about 35 to about 50 weight percent.
- 4. The fluorosilicone composition of claim 3, wherein (A) is present in an amount by weight of about 40 to about 48%.
- 5. The fluorosilicone composition of claim 1, wherein Component (B) is present in an amount ranging from about 20 to about 40 weight percent.
- 6. The fluorosilicone composition of claim 5, wherein (B) is present in an amount by weight of about 0 to about 40%.
- 7. The fluorosilicone composition of claim 1, wherein Component (C) is present in an amount ranging from about 15 to about 35 weight percent.
- 8. The fluorosilicone composition of claim 1, wherein Component (C) is present in an amount ranging from about 20 to about 30 weight percent.
- 9. The fluorosilicone composition of claim 8, wherein (C) is present in an amount by weight of about 20 to about 25%.
- 10. The fluorosilicone composition of claim 1, when the free radical generating cross-linking initiator or catalyst is present in an amount of about 1 to about 5 weight percent.
- 11. The fluorosilicone composition of claim 1, wherein the diluent is present in an amount of about 30 to about 60 weight percent solids of the total of Components (A), (B) and (C).
- 12. The fluorosilicone composition of claim 1, wherein (A) has a viscosity of at least 5000 cps at 25.degree. C. and is selected from the group consisting of a high molecular weight (HMW) fluorosilicone (FS) gum and a high molecular weight (HMW) fluorosilicone (FS) fluid.
- 13. The fluorosilicone composition of claim 12, wherein (A) contains:
- silicon bonded groups, including at least one of alkyls containing from 1 to about 8 carbon atoms; fluorochemicals including trifluoroalkyls of 1 to about 8 carbon atoms; fluoroalkyl cyclics of 1 to about 8 carbon atoms; perfluorinated alkyls of 1 to about 8 carbon atoms, perfluorinated cyclics of 1 to about 8 carbon atoms, and partially or fully fluorinated alkyl, alkenyl, ether or ester groups attached directly to backbone silicon atoms or indirectly through a diorgano siloxane segment attached to the backbone silicon atoms containing from 1 to 10 silicon atoms.
- 14. The fluorosilicone composition of claim 13, further including vinyl or silanol moieties.
- 15. The fluorosilicone composition of claim 1, wherein the resin includes M and Q units in a ratio of about 0.6:1 to about 0.9M units to 1 Q unit.
- 16. The fluorosilicone composition of claim 1, wherein the resin contains hydroxyl radicals present in the amount of about 0.2 to about 5.0 weight percent.
- 17. The fluorosilicone composition of claim 16, wherein the resin contains hydroxyl radicals present in an amount of about 1.0 to about 3.0 weight percent.
- 18. The fluorosilicone composition of claim 1, wherein the polydiorganosiloxanes having a viscosity of at least 15M cps at 25.degree. C.
- 19. The fluorosilicone composition of claim 1, wherein the diluent is selected from xylene, toluene, acetone and ethyl acetate compositions.
- 20. A pressure sensitive adhesive formed by reacting components comprising by weight:
- (A) about 5 to about 70 percent of a fluorosilicone polymer having a viscosity of at least 5000 cps at 25.degree. C.;
- (B) about 10 to about 60 percent of a resinous copolymer including R.sub.3 SiO.sub.1/2 where R is a hydrocarbon radical and SiO.sub.2 units present in a ratio of about 0.6:1 to about 0.9:1 and hydroxy radicals making up about 0.2 to about 5.0 weight percent of the total resinous copolymer weight;
- (C) about 10 to about 50 percent polydiorganosiloxanes having repeating units of the general formula SiR.sup.1 R.sup.2 O, wherein R.sup.1 and R.sup.2 are independently selected from the group consisting of an alkyl having from 1 to about 10 carbon atoms, alkenyl having from 1 to about 10 carbon atoms, an aryl and an arylalklyl;
- (D) up to about 60 weight percent of the total of Components (A), (B) and (C) of a diluent solvent; and
- (E) about 1 to 5 solids weight percent of the total of Components (A), (B) and (C) of a free radical generating initiator or catalyst, said adhesive being curable upon mixing of said free radical generating initiator or catalyst with said components (A), (B) and (C).
- 21. An adhesive as defined in claim 20, wherein Component (A) contains silanol or vinyl moieties.
- 22. An adhesive as defined in claim 20, wherein Component (A) comprises a fluorosilicone homopolymer of monomeric units of the formula SiR.sup.1 R.sup.F O wherein R.sup.1 is selected from alkyls having 1 to about 10 carbon atoms, aryl or arylalkyl, and R.sup.F is selected from partially or fully fluorinated alkyl, alkenyl, ether or ester groups.
- 23. A cured fluorosilicone pressure sensitive adhesive formed by components comprising by weight:
- (A) about 5 to about 70 percent of a fluorosilicone polymer having a viscosity of at least 500 cps at 25.degree. C.;
- (B) about 10 to about 60 percent of a resinous copolymer including R.sub.3 SiO.sub.1/2 units where R is a hydrocarbon radical and SiO.sub.e,fra 4/2.times. units present in a ratio of about 0.6:1 to about 0.9:1 and hydroxy radicals making up about 0.2 to about 5.0 weight percent of the total resinous copolymer weight;
- (C) about 10 to about 50 percent polydiorganosiloxanes having repeating units of the general formula SiR.sup.1 R.sup.2 O, wherein R.sup.1 and R.sup.2 are independently selected from the group consisting of an alkyl having from 1 to about 10 carbon atoms, alkenyl having from 1 to about 10 carbon atoms, an aryl and an arylalkyl, and the total amount of Components (A), (B) and (C) substantially equaling 100 percent by weight, and being cured into a cross-linked matrix, having trace amounts of (D) a diluent solvent; and (E) a free radical generating initiator or catalyst.
Parent Case Info
This is a continuation of application Ser. No. 07/823,234 filed on Jan. 21, 1992, now abandoned.
US Referenced Citations (11)
Foreign Referenced Citations (3)
Number |
Date |
Country |
0269454 |
Jun 1988 |
EPX |
0315333 |
Oct 1989 |
EPX |
0355991 |
Feb 1990 |
EPX |
Non-Patent Literature Citations (1)
Entry |
Noll, Chemistry and Technology of Silicones, 1968, pp. 271 to 277. |
Continuations (1)
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Number |
Date |
Country |
Parent |
823234 |
Jan 1992 |
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