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US 4,831,070 AGranted
Moldable elastomeric pressure sensitive adhesives
AssigneeDow Corning Corporation
InventorsLinda J. McInally, John T. Woodard
Life of this patent
Estimating the term…
Abstract
A composition and method for forming elastomeric pressure sensitive adhesives comprising a mixture of (A) a xylene-soluble resin copolymer of 0.6 to 0.9 triorganosiloxy units per SiO.sub.4/2 unit and having less than 0.7 weight % silicon-bonded hydroxyl units. (B) a polydiorganosiloxane fluid endcapped with silicon-bonded hydroxyl groups and having a viscosity of from about 50 to 300,000 cP. at 25.degree. C., an organosilicon compound containing an average of more than two silicon-bonded alkoxy groups per molecule, and a condensation catalyst. The cured elastomeric pressure sensitive adhesives formed from these compositions are useful as medical adhesives, such as those used for ostomy seals.
Claims23
A composition for forming elastomeric pressure sensitive adhesives comprising a homogeneous mixture of:
- (A) a xylene-soluble resin copolymer employed in an amount from 50 to 70 parts by weight, said xylene-soluble resin copolymer consisting essentially of R.sub.3 SiO.sub.1/2 units and SiO.sub.4/2 units in a mol ratio of from 0.6 to 0.9R.sub.3 SiO.sub.1/2 units for each SiO.sub.4/2 unit, wherein each R denotes, independently, a monovalent hydrocarbon radical having from 1 to 6 inclusive carbon atoms, said resin copolymer having less than 0.7 weight % silicon-bonded hydroxyl units, said resin copolymer substantially free of volatile components,
- (B) a polydiorganosiloxane fluid employed in an amount from 30 to 50 parts by weight, said polydiorganosiloxane fluid endcapped with silicon-bonded hydroxyl groups and having the average formula HO(R'.sub.2 SiO).sub.n H wherein each R' denotes, independently, a monovalent hydrocarbon or halohydrocarbon radical having from 1 to 6 inclusive carbon atoms and n has an average value so that the polydiorganosiloxane fluid has a viscosity such that the elastomeric pressure sensitive adhesive composition has a plasticity of less than 150.times.10.sup.-3 inches at 25.degree. C. without the addition of organic solvents, the total of resin copolymer (A) and polydiorganosiloxane fluid (B) being 100 parts by weight,
- (C) an alkoxy-containing organosilicon compound having an average of more than two silicon-bonded alkoxy units per molecule employed in an amount from 0.35 to 2 parts by weight,
- (D) a condensation catalyst employed in an amount from 0.5 to 13 parts by weight, and
- (E) a trimethyl-endblocked polydimethylsiloxane employed from 0 to 15 parts by weight and having a viscosity of from 10 to 1000 cSt. at 25.degree. C.
2 more elements
A composition for forming elastomeric pressure sensitive adhesives comprising a homogeneous mixture of:
- (A) a xylene-soluble resin copolymer employed in an amount from 50 to 70 parts by weight, said xylene-soluble resin copolymer consisting essentially of R.sub.3 SiO.sub.1/2 units and SiO.sub.4/2 units in a mol ratio of from 0.6 to 0.9R.sub.3 SiO.sub.1/2 units for each SiO.sub.4/2 unit, wherein each R denotes, independently, a monovalent hydrocarbon radical having from 1 to 6 inclusive carbon atoms, said resin copolymer having less than 0.7 weight % silicon-bonded hydroxyl units, said resin copolymer substantially free of volatile components,
- (B) a polydiorganosiloxane fluid employed in an amount from 30 to 50 parts by weight, said polydiorganosiloxane fluid endcapped with silicon-bonded hydroxyl groups and having the average formula HO(R'.sub.2 SiO).sub.n H wherein each R' denotes, independently, a monovalent hydrocarbon or halohydrocarbon radical having from 1 to 6 inclusive carbon atoms and n has an average value so that the polydiorganosiloxane fluid has a viscosity of from 50 to 300,000 cP. at 25.degree. C., the total of resin copolymer (A) and polydiorganosiloxane fluid (B) being 100 parts by weight,
- (C) an alkoxy-containing organosilicon compound having an average of more than two silicon-bonded alkoxy units per molecule employed in amount from 0.35 to 2 parts by weight, and
- (D) a condensation catalyst employed in an amount from 0.5 to 13 parts by weight.
1 more element
A kit for making a pressure sensitive adhesive comprising:
- a first package containing a homogeneous mixture of
- (A) a xylene-soluble resin copolymer in an amount from 50 to 70 parts by weight, said xylene-soluble resin copolymer consisting essentially of R.sub.3 SiO.sub.1/2 units and SiO.sub.4/2 units in a mol ratio of from 0.6 to 0.9R.sub.3 SiO.sub.1/2 units for each SiO.sub.4/2 unit, wherein each R denotes, independently, a monovalent hydrocarbon radical having from 1 to 6 inclusive carbon atoms, said resin copolymer having less than 0.7 weight % silicon-bonded hydroxyl units, said resin copolymer substantially free of volatile components, and
- (B) 30 to 50 parts by weight of a polydiorganosiloxane fluid endcapped with silicon-bonded hydroxyl groups and having the average formula HO(R'.sub.2 SiO).sub.n H wherein each R' denotes, independently, a monovalent hydrocarbon or halohydrocarbon radical having from 1 to 6 inclusive carbon atoms and n has an average value so that the polydiorganosiloxane fluid has a viscosity of from 50 to 300,000 cP. at 25.degree. C., the total of resin copolymer (A) and polydiorganosiloxane fluid (B) being 100 parts by weight,
- a second package containing
- (C) an alkoxy-containing organosilicon compound having an average of more than two silicon-bonded alkoxy units per molecule in an amount from 0.35 to 2 parts by weight, and
- a third package containing
- (D) a condensation catalyst in an amount from 0.5 to 13 parts by weight.
4 more elements
A kit for making a pressure sensitive adhesive comprising:
- a first package containing a homogeneous mixture of
- (A) a xylene-soluble resin copolymer in an amount from 50 to 70 parts by weight, said xylene-soluble resin copolymer consisting essentially of R.sub.3 SiO.sub.1/2 units and SiO.sub.4/2 units in a mol ratio of from 0.6 to 0.9R.sub.3 SiO.sub.1/2 units for each SiO.sub.4/2 unit, wherein each R denotes, independently, a monovalent hydrocarbon radical having from 1 to 6 inclusive carbon atoms, said resin copolymer having less than 0.7 weight % silicon-bonded hydroxyl units, said resin copolymer substantially free of volatile components,
- (B) 30 to 50 parts by weight of a polydiorganosiloxane fluid endcapped with silicon-bonded hydroxyl groups and having the average formula HO(R'.sub.2 SiO).sub.n H wherein each R' denotes, independently, a monovalent hydrocarbon or halohydrocarbon radical having from 1 to 6 inclusive carbon atoms and n has an average value so that the polydiorganosiloxane fluid has a viscosity of from 50 to 300,000 cP. at 25.degree. C., the total of resin copolymer (A) and polydiorganosiloxane fluid (B) being 100 parts by weight, and
- (C) an alkoxy-containing organosilicon compound having an average of more than two silicon-bonded alkoxy units per molecule in an amount from 0.35 to 2 parts by weight and
- a second package containing
- (D) a condensation catalyst in an amount from 0.5 to 13 parts by weight.
3 more elements
A method of forming a silicone elastomeric pressure sensitive adhesive comprising the steps of:
- (i) preparing an elastomeric pressure sensitive adhesive composition by
- (I) homogeneously mixing
- (A) 50 to 70 parts by weight of a xylene-soluble resin copolymer consisting essentially of R.sub.3 SiO.sub.1/2 units and SiO.sub.4/2 units in a mol ratio of from 0.6 to 0.9R.sub.3 SiO.sub.1/2 units for each SiO.sub.4/2 unit, wherein each R denotes, independently, a monovalent hydrocarbon radical having from 1 to 6 inclusive carbon atoms, said resin copolymer having less than 0.7 weight % silicon-bonded hydroxyl units,
- (B) 30 to 50 parts by weight of a polydiorganosiloxane fluid endcapped with silicon-bonded hydroxyl groups and having the average formula HO(R'.sub.2 SiO).sub.n H wherein each R' denotes, independently, a monovalent hydrocarbon or halohydrocarbon radical having from 1 to 6 inclusive carbon atoms and n has an average value so that the polydiorganosiloxane fluid has a viscosity such that the elastomeric pressure sensitive adhesive composition has a plasticity of less than 150.times.10.sup.-3 inches at 25.degree. C. without the addition of organic solvents, the total of resin copolymer (A) and polydiorganosiloxane fluid (B) being 100 parts by weight,
- (C) an alkoxy-containing organosilicon compound having an average of more than two silicon-bonded alkoxy units per molecule in an amount from 0.35 to 2 parts by weight,
- (D) a condensation catalyst in an amount from 0.5 to 13 parts by weight, and
- (E) no more than 15 parts by weight of a trimethyl-endblocked polydimethylsiloxane having a viscosity of from 10 to 1000 cSt. at 25.degree. C., and
- (II) devolatilizing said resin copolymer
- (A) optionally in mixture with other components wherein the mixture of resin copolymer (A) with other components is substantially non-reactive at the temperature of devolatilization,
- (ii) placing the elastomeric pressure sensitive adhesive composition in the desired form for curing, and
- (iii) curing the composition which has been placed in the desired form for curing for a sufficient time to form the elastomeric pressure sensitive adhesive.
8 more elements
A method of forming a silicone elastomeric pressure sensitive adhesive comprising the steps of:
- (i) preparing an elastomeric pressure sensitive adhesive composition by
- (I) homogeneously mixing
- (A) 50 to 70 parts by weight of a xylene-soluble resin copolymer consisting essentially of R.sub.3 SiO.sub.1/2 units and SiO.sub.4/2 units in a mol ratio of from 0.6 to 0.9R.sub.3 SiO.sub.1/2 units for each SiO.sub.4/2 unit, wherein each R denotes, independently, a monovalent hydrocarbon radical having from 1 to 6 inclusive carbon atoms, said resin copolymer having less than 0.7 weight % silicon-bonded hydroxyl units,
- (B) 30 to 50 parts by weight of a polydiorganosiloxane fluid endcapped with silicon-bonded hydroxyl groups and having the average formula HO(R'.sub.2 SiO).sub.n H wherein each R' denotes, independently, a monovalent hydrocarbon or halohydrocarbon radical having from 1 to 6 inclusive carbon atoms and n has an average value so that the polydiorganosiloxane fluid has a viscosity of from 50 to 300,000 cP. at 25.degree. C., the total of resin copolymer (A) and polydiorganosiloxane fluid (B) being 100 parts by weight, and
- (C) an alkoxy-containing organosilicon compound having an average of more than two silicon-bonded alkoxy units per molecule in an amount from 0.35 to 2 parts by weight,
- (D) a condensation catalyst in an amount from 0.5 to 13 parts by weight,
- (E) 0 to 15 parts by weight of a trimethyl-endblocked polydimethylsiloxane having a viscosity of from 10 to 1000 cSt. at 25.degree. C., and
- (II) devolatilizing said resin copolymer (A) optionally in mixture with other components wherein said mixture of resin copolymer (A) with other components is substantially non-reactive at the temperature of devolatilization,
- (ii) placing the elastomeric pressure sensitive adhesive composition in the desired form for curing, and
- (iii) curing the composition which has been placed in the desired form for curing for a sufficient time to form the elastomeric pressure sensitive adhesive.
7 more elements
Dependencies are inferred from the claim text.