US4687829A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of adjusting physical properties in silicone elastomeric sealant
Assignee: Dow Silicones Corp
•
Filing: 1986-03-03
•
Granted: 1987-08-18
•
Expires: 2006-03-03
Abstract
Abstract An improved silicone elastomeric sealant composition is produced by mixing alkoxy functional polydiorganosiloxane having alkoxysilethylene ends with a combination of trifunctional or tetrafunctional silane crosslinker and defunctional silane chain extender. The sealant composition is stable upon storage in the absence of moisture, but cures to an elastomer upon exposure to moisture. The cured composition can be adjusted for the desired elongation by varying the ratio of crosslinker to chain extender, but there must be at least 50 mol percent of crosslinker in the composition to ensure that the composition cures to a non-tacky surface.
Inventors
- 👤 Roger G. Chaffee
- 👤 Leo F. Stebleton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:16
CPC Classifications
C; C09; C09K; C09K3/00; C09K3/10; C09K3/1006; C09K3/1018; C08; C08K; C08K5/00; C08K5/54; C08K5/541; C08K5/5415; C08L; C08L83/00; C08L83/14; Y; Y10; Y10S; Y10S528/00; Y10S528/901
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
221 words
A method of adjusting the physical properties of a silicone elastomeric sealant, having alkoxy functional groups, which is stable in the absence of moisture and cures upon exposure to moisture comprising (A) mixing in the absence of moisture (1) 100 parts by weight of an alkoxy functional polydiorganosiloxane of the formula ##STR11## where R is methyl, ethyl, propyl, phenyl, or trifluoropropyl, R" is methyl or ethyl, a is 0 or 1, b is 0 or 1, c is from 1 to 6 and x is such that the viscosity is from 1 to 1000 Pa.s at 25° C., (2) From 0 to 500 parts by weight of a filler, (3) from 2 to 15 parts by weight of a crosslinker of the formula R'.sub.a Si(OR").sub.4-a where R' is methyl or phenyl, R" is methyl or ethyl, and a is 0 or 1, (4) from 1 to 15 parts by weight of a chain extender selected from the formula PhMeSi(OR") 2 , R"OSiMe 2 OR", and Ph(OSiMe 3 )Si(OR") 2 , where Ph is phenyl, Me is methyl, and R" is methyl or ethyl, and the mols of chain extender (4) are less than the mols of crosslinker (3), and (5) from 0.2 to 4.0 parts by weight of a titanium catalyst, and (B) storing the mixture in the absence of moisture.
Claim 2
Independent Claim
221 words
A method of adjusting the physical properties of a silicone elastomeric sealant, having alkoxy functional groups, which is stable in the absence of moisture and cures upon exposure to moisture comprising (A) mixing in the absence of moisture (1) 100 parts by weight of an alkoxy functional polydiorganosiloxane of the formula ##STR11## where R is methyl, ethyl, propyl, phenyl, or trifluoropropyl, R" is methyl or ethyl, a is 0 or 1, b is 0 or 1, c is from 1 to 6 and x is such that the viscosity is from 1 to 1000 Pa.s at 25° C., (2) From 0 to 500 parts by weight of a filler, (3) from 2 to 15 parts by weight of a crosslinker of the formula R'.sub.a Si(OR").sub.4-a where R' is methyl or phenyl, R" is methyl or ethyl, and a is 0 or 1, (4) from 1 to 15 parts by weight of a chain extender selected from the formula PhMeSi(OR") 2 , R"OSiMe 2 OR", and Ph(OSiMe 3 )Si(OR") 2 , where Ph is phenyl, Me is methyl, and R" is methyl or ethyl, and the mols of chain extender (4) are less than the mols of crosslinker (3), and (5) from 0.2 to 4.0 parts by weight of a titanium catalyst, and (B) storing the mixture in the absence of moisture.
Claim 3
Dependent Claim
10 words
The method of claim 1 in which b is 1.
Claim 4
Dependent Claim
10 words
The method of claim 2 in which c is 1.
Claim 5
Dependent Claim
12 words
The method of claim 1 in which the crosslinker (3) is trifunctional.
Claim 6
Dependent Claim
13 words
The method of claim 1 in which the chain extender (4) is phenyl(trimethylsiloxy)dimethoxysilane.
Claim 7
Dependent Claim
13 words
The method of claim 1 in which the chain extender (4) is dimethyldimethoxysilane.
Claim 8
Dependent Claim
46 words
The method of claim 2 in which the crosslinker (3) is present in an amount of from 2 to 8 parts by weight and is methyltrimethoxysilane and chain extender (4) is present in an amount of from 1 to 4 parts by weight and is phenyl(trimethylsiloxy)dimethoxysilane.
Claim 9
Dependent Claim
46 words
The method of claim 3 in which the crosslinker (3) is present in an amount of from 2 to 8 parts by weight and is methyltrimethoxysilane and chain extender (4) is present in an amount of from 1 to 4 parts by weight and is phenyl(trimethylsiloxy)dimethoxysilane.
Claim 10
Dependent Claim
9 words
The composition produced by the method of claim 1.
Claim 11
Dependent Claim
9 words
The composition produced by the method of claim 2.
Claim 12
Dependent Claim
9 words
The composition produced by the method of claim 3.
Claim 13
Dependent Claim
9 words
The composition produced by the method of claim 4.
Claim 14
Dependent Claim
9 words
The composition produced by the method of claim 5.
Claim 15
Dependent Claim
9 words
The composition produced by the method of claim 6.
Claim 16
Dependent Claim
9 words
The composition produced by the method of claim 7.
Claim 17
Dependent Claim
9 words
The composition produced by the method of claim 8.
References Cited (Backward Citations)
US3122522A
Cited
US3175993A
Cited
US3383355A
Cited
US3334067A
Cited
US3542901A
Cited
US3856839A
Cited
US4100129A
Cited
US4143088A
Cited
EP0110251A2
Cited
US4599394A
Cited
EP0123935A2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-17 | 1991-02-16 | 1991-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-17 | 1995-02-16 | 1995-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-17 | 1999-02-16 | 1999-08-18 | $7700.00 | Window Closed / Lapsed |