US4269740A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing elastomeric particles free of agglomeration
Assignee: Zeon Chemical LP
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Filing: 1979-09-28
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Granted: 1981-05-26
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Expires: 1999-09-28
Abstract
Abstract This invention relates to a process of producing elastomeric particles, such as those of natural and synthetic powdered and crumb rubbers and to the compositions prepared in accordance with such process. Specifically, the invention comprises encapsulating the elastomeric particles with a coating or film of a preplasticized vinyl resin, such as, for example, polymers and copolymers of vinyl and vinylidene halides and the like. The resultant composite particles are free-flowing and free of irreversible agglomeration and can be used in dry-blending with other materials prior to being formed into useful articles.
Inventors
- 👤 Martin E. Woods
- 👤 Daniel M. Chang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:35
CPC Classifications
C; C22; C22C; C22C18/00; C08; C08J; C08J3/00; C08J3/12; C08J3/124; C08L; C08L9/00; C08L9/02; C08L9/06; C08J2321/00; C08L27/00; C08L27/02; C08L27/04; C08L27/06
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
154 words
The process of producing elastomer particles in the form of dry, non-agglomerating powders or crumbs which comprises, forming a dispersion of elastomer particles in an aqueous medium containing from about 15% to about 40% by weight of total solids, adding thereto with agitation an aqueous dispersion of a preplasticized resin latex containing from about 20% to about 60% by weight of total solids, said resin being selected from preplasticized homopolymers and copolymers of vinyl and vinylidene halides, adding to the combined dispersions a coagulating agent in an aqueous medium with agitation whereby said resin is precipitated in the form of a film on said elastomer particles thereby encapsulating said particles with said resin, continuing the agitation for a period of about 15 to about 90 minutes, and then separating the encapsulated particles from the aqueous medium and drying the same, said dried encapsulated particles being such that they do not irreversibly agglomerate upon storage.
Claim 2
Dependent Claim
154 words
The process of producing elastomer particles in the form of dry, non-agglomerating powders or crumbs which comprises, forming a dispersion of elastomer particles in an aqueous medium containing from about 15% to about 40% by weight of total solids, adding thereto with agitation an aqueous dispersion of a preplasticized resin latex containing from about 20% to about 60% by weight of total solids, said resin being selected from preplasticized homopolymers and copolymers of vinyl and vinylidene halides, adding to the combined dispersions a coagulating agent in an aqueous medium with agitation whereby said resin is precipitated in the form of a film on said elastomer particles thereby encapsulating said particles with said resin, continuing the agitation for a period of about 15 to about 90 minutes, and then separating the encapsulated particles from the aqueous medium and drying the same, said dried encapsulated particles being such that they do not irreversibly agglomerate upon storage.
Claim 3
Dependent Claim
14 words
The process as defined in claim 1 wherein the vinyl resin is polyvinyl chloride.
Claim 4
Dependent Claim
20 words
The process as defined in claim 1 wherein the vinyl resin is a copolymer of vinyl chloride and vinyl acetate.
Claim 5
Dependent Claim
13 words
The process as defined in claim 1 wherein the elastomer is natural rubber.
Claim 6
Dependent Claim
17 words
The process as defined in claim 1 wherein the elastomer is a copolymer of styrene and butadiene.
Claim 7
Dependent Claim
18 words
The process as defined in claim 1 wherein the elastomer is a copolymer of acrylonitrile, butadiene, and styrene.
Claim 8
Dependent Claim
12 words
The process as defined in claim 1 wherein the elastomer is neoprene.
Claim 9
Dependent Claim
32 words
The process as defined in claim 1 wherein the preplasticized vinyl resin is made by polymerizing vinyl chloride in the presence of a plasticizer selected from organic phosphoric esters and phthalic esters.
Claim 10
Dependent Claim
13 words
The process as defined in claim 8 wherein the plasticizer is dioctyl phthalate.
Claim 11
Dependent Claim
27 words
The process as defined in claim 1 wherein the coagulating agent is an aqueous solution containing from about 2.0% to about 10.0% by weight of calcium chloride.
Claim 12
Dependent Claim
14 words
The process as defined in claim 10 wherein the vinyl resin is polyvinyl chloride.
Claim 13
Dependent Claim
17 words
The process as defined in claim 11 wherein the elastomer is a copolymer of butadiene and acrylonitrile.
Claim 14
Dependent Claim
31 words
The process as defined in claim 12 wherein the polyvinyl chloride is made by polymerizing vinyl chloride in the presence of a plasticizer selected from organic phosphoric esters and phthalic esters.
Claim 15
Dependent Claim
13 words
The process as defined in claim 13 wherein the plasticizer is dioctyl phthalate.
Claim 16
Dependent Claim
17 words
The process as defined in claim 1 wherein the elastomer is a copolymer of butadiene and acrylonitrile.
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) | 1984-05-25 | 1984-11-24 | 1985-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-05-25 | 1988-11-24 | 1989-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-05-25 | 1992-11-24 | 1993-05-26 | $7700.00 | Window Closed / Lapsed |