US4244849A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silicone emulsion which provides an elastomeric product and methods for preparation
Assignee: Dow Silicones Corp
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Filing: 1979-08-06
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Granted: 1981-01-13
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Expires: 1999-08-06
Abstract
Abstract An aqueous silicone emulsion is described which provides an elastomeric product upon removal of the water under ambient conditions. The emulsion comprises a continuous water phase and an anionically stabilized dispersed silicone phase which is a graft copolymer of a hydroxyl endblocked polydiorganosiloxane and an alkali metal silicate. The emulsion is formed and maintained in a stable condition by control of the pH within the range of 8.5 to 12 inclusive. In the method of preparing the emulsion, an organic tin compound can be employed to accelerate the formation of the graft copolymer.
Inventors
- 👤 John C. Saam
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:24
CPC Classifications
C; C08; C08L; C08L83/00; C08L83/10; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31652; Y10T428/31663; Y10T428/31667
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
81 words
An aqueous silicone emulsion comprising a continuous water phase and a dispersed silicone phase free of colloidal silica prepared by (A) adding alkali metal silicate to anionically stabilized aqueous emulsion of hydroxyl endblocked polydiorganosiloxane, (B) adjusting the pH of the emulsion within the range from 8.5 to 12 inclusive, and (C) then aging the emulsion at the pH of 8.5 to 12 for a time period such that an elastomeric product is formed upon removal of the water under ambient conditions.
Claim 2
Dependent Claim
81 words
An aqueous silicone emulsion comprising a continuous water phase and a dispersed silicone phase free of colloidal silica prepared by (A) adding alkali metal silicate to anionically stabilized aqueous emulsion of hydroxyl endblocked polydiorganosiloxane, (B) adjusting the pH of the emulsion within the range from 8.5 to 12 inclusive, and (C) then aging the emulsion at the pH of 8.5 to 12 for a time period such that an elastomeric product is formed upon removal of the water under ambient conditions.
Claim 3
Dependent Claim
14 words
The silicone emulsion according to claim 1 in which the polydiorganosiloxane is a polydimethylsiloxane.
Claim 4
Dependent Claim
38 words
The silicone emulsion according to claim 2 in which the alkali metal silicate is a sodium silicate and is employed in an amount of from 0.3 to 30 parts by weight per each 100 parts by weight polydimethylsiloxane.
Claim 5
Dependent Claim
22 words
The silicone emulsion according to claim 3 in which the polydimethylsiloxane employed has a weight average molecular weight of 200,000 to 700,000.
Claim 6
Dependent Claim
17 words
The silicone emulsion according to claim 4 in which there is also present an organic tin salt.
Claim 7
Dependent Claim
37 words
The silicone emulsion according to claim 5 in which the organic tin salt is a diorganotindicarboxylate and is present in an amount of from 0.1 to 2 parts by weight for each 100 parts by weight polydimethylsiloxane.
Claim 8
Dependent Claim
15 words
The silicone emulsion according to claim 6 in which there is also present a filler.
Claim 9
Dependent Claim
19 words
The silicone emulsion according to claim 4 in which the hydroxyl endblocked polydimethylsiloxane is an anionic emulsion polymerized polydimethylsiloxane.
Claim 10
Dependent Claim
63 words
An aqueous silicone emulsion which provides an elastomeric product upon removal of the water under ambient conditions comprising a continuous water phase and an anionically stabilized dispersed silicone phase free of colloidal silica, the silicone phase comprising a graft copolymer of alkali metal silicate and a hydroxyl endblocked polydiorganosiloxane, the silicone emulsion having a pH within the range from 8.5 to 12 inclusive.
Claim 11
Dependent Claim
63 words
An aqueous silicone emulsion which provides an elastomeric product upon removal of the water under ambient conditions comprising a continuous water phase and an anionically stabilized dispersed silicone phase free of colloidal silica, the silicone phase comprising a graft copolymer of alkali metal silicate and a hydroxyl endblocked polydiorganosiloxane, the silicone emulsion having a pH within the range from 8.5 to 12 inclusive.
Claim 12
Dependent Claim
27 words
The silicone emulsion according to claim 9 in which the polydiorganosiloxane is an anionic emulsion polymerized polydimethylsiloxane having a weight average molecular weight of 200,000 to 700,000.
Claim 13
Dependent Claim
38 words
The silicone emulsion according to claim 10 in which the alkali metal silicate is a sodium silicate and is employed in an amount of from 0.3 to 30 parts by weight for each 100 parts by weight polydimethylsiloxane.
Claim 14
Dependent Claim
31 words
The silicone emulsion according to claim 11 in which a diorganotindicarboxylate is present in an amount of from 0.1 to 2 parts by weight for each 100 parts by weight polydimethylsiloxane.
Claim 15
Dependent Claim
23 words
The silicone emulsion according to claims 6 or 12 in which the emulsion has a pH within the range from 10 to 12.
Claim 16
Dependent Claim
15 words
The silicone emulsion according to claim 13 in which there is also present a filler.
Claim 17
Independent Claim
75 words
A method of preparing an aqueous silicone emulsion comprising (A) adding alkali metal silicate free of colloidal silica to an anionically stabilized aqueous emulsion of hydroxyl endblocked polydiorganosiloxane, (B) adjusting the pH of the emulsion within the range from 8.5 to 12 inclusive, and (C) then aging the emulsion at the pH of 8.5 to 12 for a time period such that an elastomeric product is formed upon removal of the water under ambient conditions.
Claim 18
Independent Claim
75 words
A method of preparing an aqueous silicone emulsion comprising (A) adding alkali metal silicate free of colloidal silica to an anionically stabilized aqueous emulsion of hydroxyl endblocked polydiorganosiloxane, (B) adjusting the pH of the emulsion within the range from 8.5 to 12 inclusive, and (C) then aging the emulsion at the pH of 8.5 to 12 for a time period such that an elastomeric product is formed upon removal of the water under ambient conditions.
Claim 19
Dependent Claim
34 words
The method according to claim 15 in which the emulsion of polydiorganosiloxane is prepared by anionic emulsion polymerization of a siloxane selected from the group consisting of polydiorganosiloxane cyclics and hydroxyl endblocked polydiorganosiloxane oligomers.
Claim 20
Dependent Claim
16 words
The method according to claim 15 additionally comprising adding an organic tin salt to the emulsion.
Claim 21
Dependent Claim
32 words
The silicone emulsion according to claim 1 in which the combined amount of silicate and polydiorganosiloxane employed is 67 to 160 parts by weight for each 100 parts by weight of water.
Claim 22
Dependent Claim
32 words
The silicone emulsion according to claim 9 in which the graft copolymer is employed in an amount of from 67 to 160 parts by weight for each 100 parts by weight water.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-01-13 | 1984-07-14 | 1985-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-13 | 1988-07-14 | 1989-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-13 | 1992-07-14 | 1993-01-13 | $7700.00 | Window Closed / Lapsed |