Patent US4228256A successfully refreshed from Google Patents.
US4228256A
Expired / Lapsed
US
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Transparent blends of resinous copolymers and grafted elastomers
Assignee: Cy/Ro Industries
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Filing: 1978-09-18
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Granted: 1980-10-14
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Expires: 1998-09-18
Abstract
Abstract The use of a sequential and controlled addition of monomers during grafting to produce grafted elastomers results in blends of the grafted elastomer and a resinuous copolymer which have superior optical properties.
Inventors
- 👤 Joseph M. Schmitt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:32
CPC Classifications
C; C08; C08L; C08L33/00; C08L33/04; C08L33/06; C08L33/10; C08L33/12; C08L2205/00; C08L2205/22; C08L51/00; C08L51/04
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
82 words
A method of preparing a non-agglomerating, readily dispersible grafted rubber comprising: (1) placing a rubber latex in a reaction vessel; (2) adding thereto one or more monomers to be grafted thereon; (3) equilibrating said rubber latex; (4) controllably adding to said equilibrated rubber latex and said monomers at least one monomer to be grafted thereon, wherein the addition of said monomer takes at least 15 minutes and is in the substantial absence of added emulsifier; during which time a grafting reaction occurs.
Claim 2
Independent Claim
82 words
A method of preparing a non-agglomerating, readily dispersible grafted rubber comprising: (1) placing a rubber latex in a reaction vessel; (2) adding thereto one or more monomers to be grafted thereon; (3) equilibrating said rubber latex; (4) controllably adding to said equilibrated rubber latex and said monomers at least one monomer to be grafted thereon, wherein the addition of said monomer takes at least 15 minutes and is in the substantial absence of added emulsifier; during which time a grafting reaction occurs.
Claim 3
Dependent Claim
11 words
The method of claim 1 wherein a redox initiator is used.
Claim 4
Dependent Claim
30 words
The method of claim 2 wherein either the reductant or the oxidant portion of the initiator is controllably added at the same time as the monomer which is controllably added.
Claim 5
Dependent Claim
23 words
The method of claim 1 wherein one or more other graftable monomers are placed in the reaction vessel along with the rubber latex.
Claim 6
Dependent Claim
22 words
The method of claim 4 wherein said other graftable monomers are styrene and optionally a monomer selected from methylacrylate, ethylacrylate and acrylonitrile.
Claim 7
Dependent Claim
18 words
The method of claim 1 wherein the rubber latex is polybutadiene and the monomer controllably added is methylmethacrylate.
Claim 8
Dependent Claim
16 words
The method of claim 1 wherein a pH of from about 6 to 8.5 is used.
Claim 9
Dependent Claim
16 words
The method of claim 1 wherein a temperature of about 20° to 65° C. is used.
References Cited (Backward Citations)
US3849358A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-10-14 | 1984-04-14 | 1984-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-14 | 1988-04-14 | 1988-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-14 | 1992-04-14 | 1992-10-14 | $7700.00 | Window Closed / Lapsed |