US5425947A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Curable filled polysiloxane compositions
Assignee: Dow Silicones Belgium SPRL
•
Filing: 1992-11-19
•
Granted: 1995-06-20
•
Expires: 2012-11-19
Abstract
Abstract The specification describes and claims a moisture curable composition comprising hydroxypolysiloxane, silane curing agent, finely divided filler (preferably calcium carbonate), catalyst, and as rheological additive, a polymer having on its polymer chain at least one carboxylic acid anhydride group. Preferred rheological additives are polybutadiene polymers treated with e.g. maleic acid anhydride. These products have improved rheology for sealant use.
Inventors
- 👤 Jean-Paul Hautekeer
- 👤 Patrick Leempoel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 02:48
CPC Classifications
C; C08; C08L; C08L83/00; C08L83/04; C08G; C08G77/00; C08G77/04; C08G77/14; C08G77/16; C08G77/18; C08G77/20; C08G77/70
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
58 words
A curable composition comprising the product formed by mixing a hydroxypolysiloxane with a silane or siloxane curing agent therefor, finely divided filler, a catalyst for promoting curing of the product in presence of moisture of the atmosphere and a rheological additive comprising a polymer having in or on its polymer chain at least one carboxylic acid anhydride group.
Claim 2
Dependent Claim
58 words
A curable composition comprising the product formed by mixing a hydroxypolysiloxane with a silane or siloxane curing agent therefor, finely divided filler, a catalyst for promoting curing of the product in presence of moisture of the atmosphere and a rheological additive comprising a polymer having in or on its polymer chain at least one carboxylic acid anhydride group.
Claim 3
Dependent Claim
22 words
A composition according to claim 1 wherein the rheological additive is a liquid or low melting point solid at normal working temperature.
Claim 4
Dependent Claim
59 words
A composition according to claim 1 wherein the rheological additive comprises a polybutadiene polymer which has been treated with a carboxylic acid anhydride and has a viscosity in the range 1,500 to 20,000 mm 2 /s, an acid number (mg KOH/g) in the range 50 to 200 and an average of between 1 and 7 anhydride groups per molecule.
Claim 5
Dependent Claim
15 words
A composition according to claim 3 wherein the carboxylic acid anhydride is maleic acid anhydride.
Claim 6
Dependent Claim
15 words
A composition according to claim 1 wherein the filler comprises precipitated and/or ground calcium carbonate.
Claim 7
Dependent Claim
88 words
A composition according to claim 1 wherein the filler is present to an extent of 150 to 250 parts by weight per 100 parts by weight of the hydroxypolysiloxane and comprises a mixture of (i) a calcium carbonate composed principally of particles having a surface area of 20 m 2 /g and (ii) a calcium carbonate composed principally of particles having a surface area of 1 to 2 m 2 /g, in a ratio of from 1 to 3 parts by weight of (i) per part of (ii).
Claim 8
Dependent Claim
51 words
A composition according to claim 1 wherein the product is formed by mixing the said ingredients and an alkyl or an arylalkyl sulphonic acid, of the general formula RSO 3 H where R represents R'C 6 H 4 in which R' is an alkyl group containing 6 to 18 carbon atoms.
Claim 9
Dependent Claim
54 words
A composition according to claim 1 wherein the hydroxypolysiloxane comprises a dihydroxypolysiloxane of the general formula HO(R 2 SiO) x H wherein R represents a monovalent hydrocarbon group having up to 12 carbon atoms, x is an integer such that the polymer has a viscosity in the range 50 to 500,000 mm 2 /s.
Claim 10
Dependent Claim
12 words
A composition according to claim 1 wherein the curing agent comprises methyltrimethoxysilane.
Claim 11
Dependent Claim
45 words
A composition according to claim 1 wherein the product is formed by mixing the said ingredients and up to 25% by weight of the composition of a trialkylsilyl endblocked polydimethylsiloxane having a viscosity in the range 100 mm 2 /s to 15,000 mm 2 /s.
References Cited (Backward Citations)
US3943085A
Cited
US3770687A
Cited
US4251616A
Cited
JPS55108458A
Cited
US4395524A
Cited
US4393161A
Cited
US4785039A
Cited
US4808251A
Cited
US5200461A
Cited
US4867896A
Cited
US4925890A
Cited
US4987170A
Cited
US5104925A
Cited
US4898910A
Cited
US4962152A
Cited
US5063114A
Cited
US5202190A
Cited
US5132350A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-06-19 | 1998-12-19 | 1999-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-06-19 | 2002-12-19 | 2003-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-06-19 | 2006-12-19 | 2007-06-20 | $7700.00 | Window Closed / Lapsed |