Patent US4090015A successfully refreshed from Google Patents.
US4090015A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for polymerizing dienic monomers
Assignee: Shin-Etsu Chemical Co Ltd
•
Filing: 1977-07-25
•
Granted: 1978-05-16
•
Expires: 1997-07-25
Abstract
Abstract In the emulsion polymerization of a dienic monomer or a mixture containing a dienic monomer and at least one other copolymerizable monomer in an aqueous medium, the deposition of polymer scale on the inner walls of the polymerization reactor and other surfaces in contact with the monomer or monomeric mixture can be remarkably reduced or prevented by providing coating layers of an organopolysiloxane on those surfaces, prior to the polymerization, by applying the organopolysiloxane directly to the surfaces or by applying one or a mixture of hydrolyzable organosilanes to the surfaces, followed by hydrolysis-condensation of the silanes, to form the organopolysiloxane in situ.
Inventors
- 👤 Shunichi Koyanagi
- 👤 Niichiro Hasegawa
- 👤 Toshihide Shimizu
- 👤 Ichiro Kaneko
- 👤 Sensaku Katsushima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:38
CPC Classifications
C; C08; C08F; C08F2/00; C08F2/002; C08F2/004
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
70 words
In a method for preparing a polymer with dienic monomer units in a weight fraction of at least 5% by emulsion polymerization in an aqueous medium in the presence of an emulsifier and a polymerization initiator in a polymerization reactor, the improvement comprising forming a coating layer of an organopolysiloxane on the surfaces of the inner walls of the polymerization reactor and other instruments in contact with the polymerization mixture.
Claim 2
Dependent Claim
70 words
In a method for preparing a polymer with dienic monomer units in a weight fraction of at least 5% by emulsion polymerization in an aqueous medium in the presence of an emulsifier and a polymerization initiator in a polymerization reactor, the improvement comprising forming a coating layer of an organopolysiloxane on the surfaces of the inner walls of the polymerization reactor and other instruments in contact with the polymerization mixture.
Claim 3
Dependent Claim
29 words
The method as claimed in claim 1 wherein the formation of said coating layer is carried out by applying a solution or dispersion of the organopolysiloxane to said surfaces.
Claim 4
Dependent Claim
38 words
The method as claimed in claim 1 wherein the formation of said coating layer is carried out by applying a solution or dispersion of at least one hydrolyzable organosilane to said surfaces and hydrolysiscondensating said organosilane in situ.
Claim 5
Dependent Claim
14 words
The method as claimed in claim 1 wherein said organopolysiloxane is curable by crosslinking.
Claim 6
Dependent Claim
31 words
The method as claimed in claim 1 wherein said organopolysiloxane contains methyl groups in an amount of at least 50 mole % of all organic groups bonded to the silicon atoms.
Claim 7
Dependent Claim
14 words
The method as claimed in claim 1 wherein said organopolysiloxane is an alkali silanolate.
Claim 8
Dependent Claim
26 words
The method as claimed in claim 1 wherein the amount of said coating layer formed on said surfaces is at least 0.001 g/m 2 as dried.
Claim 9
Dependent Claim
20 words
The method as claimed in claim 1 wherein said same or different organopolysiloxane is additionally added to the polymerization mixture.
Claim 10
Dependent Claim
18 words
The method as claimed in claim 1 wherein said organopolysiloxane is a methylhydrogenpolysiloxane fluid admixed a curing catalyst.
Claim 11
Dependent Claim
15 words
The method as claimed in claim 1 wherein said organopolysiloxane is a room-temperature-vulcanizing silicone elastomer.
Claim 12
Dependent Claim
18 words
The method as claimed in claim 1 wherein said organopolysiloxane is an organopolysiloxane resin curable at room temperature.
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) | 1981-05-15 | 1981-11-14 | 1982-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-15 | 1985-11-14 | 1986-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-15 | 1989-11-14 | 1990-05-16 | $7700.00 | Window Closed / Lapsed |