Patent US3697493A successfully refreshed from Google Patents.
US3697493A
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Preparation of polyvinylchloride
Assignee: Dynamit Nobel AG
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Filing: 1969-03-27
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Granted: 1972-10-10
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Expires: 1989-03-27
Abstract
Abstract Process for preparing an improved polyvinyl chloride comprising polymerizing vinyl chloride in the presence of a peroxide and/or azo compound as catalyst, a protective colloid and in the additional presence of 1 to 20 weight percent referred to the vinylchloride of a polyvinylchloride including an emulsifier, the polyvinyl chloride having a particle size of 0.03 to 2.0 Mu , introducing a salt of a bivalent or trivalent metal to precipitate the emulsifier which has been introduced with the polyvinylchloride emulsion, and recovering the polyvinylchloride product of improved properties thereby formed.
Inventors
- 👤 Gunther Meyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 05:00
CPC Classifications
C; C08; C08F; C08F259/00; C08F259/02; C08F259/04; Y; Y10; Y10S; Y10S526/00; Y10S526/909; Y10S526/91
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
34 words
Process according to claim 1 wherein said polyvinylchloride is present in an amount of 3 to 8 weight percent referred to the vinylchloride monomer and said polymerization is carried out at 30* to 80*C.
Claim 2
Dependent Claim
18 words
Process according to claim 1 wherein said polyvinylchloride has a particle size of 0.3 to 0.5 Mu .
Claim 3
Dependent Claim
15 words
Process according to claim 1 wherein said polyvinylchloride is in the form of a latex.
Claim 4
Dependent Claim
20 words
Process according to claim 4 wherein said latex has a solids content of between 20 and 60 percent by weight.
Claim 5
Dependent Claim
29 words
Process according to claim 1 wherein said catalyst is a member selected from the group consisting of lauroyl peroxide, caproyl peroxide, benzoyl peroxide, keto peroxide, persulfates, and azoisobutyric acid.
Claim 6
Dependent Claim
30 words
Process according to claim 1 wherein said protective colloid is a member selected from the group consisting of methyl cellulose, gelatin water-soluble starches, polyvinyl alcohols, polyacrylic acid, talc and kaolin.
Claim 7
Dependent Claim
31 words
Process according to claim 1 wherein said salt is a member selected from the group consisting of chlorides, sulfates, nitrates and acetates of calcium, magnesium, aluminum, strontium, barium, tin and zinc.
Claim 8
Dependent Claim
46 words
Process according to claim 1 wherein there is additionally present a monomer selected from the group consisting of vinyl acetate, vinylidene chloride, vinyl ether, acrylonitrile, acrylic acid ester and methacrylic acid ester in an amount of up to 10 percent by weight of total monomer present.
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) | 1975-10-10 | 1976-04-10 | 1976-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-10 | 1980-04-10 | 1980-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-10 | 1984-04-10 | 1984-10-10 | $7700.00 | Window Closed / Lapsed |