US3706705A
Expired / Lapsed
US
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Method for suspension-polymerizing vinyl chloride
Assignee: Shin-Etsu Chemical Co Ltd
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Filing: 1971-08-26
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Granted: 1972-12-19
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Expires: 1991-08-26
Abstract
Abstract Vinyl chloride or a mixture of vinyl monomers containing vinyl chloride as its main component, and an aqueous medium containing a protective colloidal substance and an anionic surface active agent are subjected to an initial stirring, in the presence of an oil-soluble catalyst. Before the rate degree of conversion reaches 30 percent, an inorganic polyvalent metal salt and/or an amine hydrochloride is added to the polymerization system. The anionic surface active agent is thereby rendered water-insoluble. The polymerization is then completed. A polymer having uniform particle size distribution, superior porosity and a high rate of plasticizer absorption is produced.
Inventors
- 👤 Shunichi Koyanagi
- 👤 Hajime Kitamura
- 👤 Toshihide Shimizu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:11
CPC Classifications
C; C08; C08F; C08F14/00; C08F14/02; C08F14/04; C08F14/06
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
34 words
The method as claimed in claim 1 wherein the inorganic polyvalent metal salt, the amine hydrochloride or the inorganic polyvalent metal salt and the amine hydrochloride is added before the start of the polymerization.
Claim 2
Dependent Claim
30 words
The method as claimed in claim 1 wherein said inorganic polyvalent metal salt is a chloride, hydroxide, oxide, carbonate or acetate of calcium, magnesium, zinc, lead, tin, aluminum or titanium.
Claim 3
Dependent Claim
50 words
The method as claimed in claim 1 wherein the protective colloid and the anionic surfactant are present in a weight ratio of 1:4 to 4:1 respectively and the total amount of the protective colloid and the anionic surfactant employed is 0.01 to 1.0 percent by weight, based on monomer weight.
Claim 4
Dependent Claim
50 words
The method as claimed in claim 1 wherein the protective colloid and the anionic surfactant are present in a weight ratio of 1:1 to 1:4 respectively and the total amount of the protective colloid and the anionic surfactant employed is 0.1 to 0.5 percent by weight, based on monomer weight.
Claim 5
Dependent Claim
61 words
The method as claimed in claim 1 wherein said catalyst is an organic peroxide selected from the group consisting of benzoyl peroxide, caproyl peroxide, lauroyl peroxide, 2,4-dichlorobenzoyl peroxide, diisopropyl peroxy-dicarbonate, di-2 ethylhexyl peroxydicarbonate, dicyclohexyl peroxydicarbonate, ter-butyl peroxypivalate, acetylcyclohexyl sulfonyl peroxide, or an azo compound selected from the group consisting of Alpha , Alpha ''-azobisisobutyronitrile, Alpha , Alpha ''-azobis 2,4-dimethylvaleronitrile and azobis-4-methoxy-2,4-dimethyl-valeronitrile.
Claim 6
Dependent Claim
45 words
The method as claimed in claim 1 wherein the protective colloid is selected from the group consisting of cellulose ethers, polyvinyl alcohol, partially saponified polyvinyl acetate, styrene-maleic anhydride copolymer, vinyl acetate-maleic anhydride copolymer, partially saponified substance of polyacrylic ester or methacrylic ester, gelatin and starch.
Claim 7
Dependent Claim
25 words
The process as claimed in claim 7 wherein said cellulose ethers are methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxy-propyl methylcellulose and carboxy methylcellulose.
Claim 8
Dependent Claim
43 words
The process as claimed in claim 1 wherein said anionic surfactant is selected from the group consisting of the potassium, sodium or ammonium salt of oleic or lauric acid, sodium lauryl sulfate, ammonium lauryl sulfate, dodecylbenzene sodium sulfonate, dodecylnaphthalene sodium sulfonate, dioctyl sulfosuccinate.
Claim 9
Dependent Claim
88 words
The process as claimed in claim 1 wherein said another monomer is selected from the group consisting of Alpha -olefins, vinyl esters, vinyl ethers, acrylic acid, methacrylic acid, acrylic acid esters, methacrylic acid esters, vinyl halides excepting vinyl chloride, aromatic vinyl compounds, maleic acid, maleic acid anhydride, fumaric acid, fumaric acid ester, vinylidene chloride and acrylonitrile and said mixture of vinyl chloride and another monomer contains from 50 to 1 part by weight of said another monomer and 50 to 99 parts by weight of said vinyl chloride.
Claim 10
Dependent Claim
61 words
The process as claimed in claim 9 wherein said Alpha -olefins are ethylene and propylene; said vinyl esters are vinyl acetate and vinyl stearate; said vinyl ethers are methyl vinyl ether and cetyl vinyl ether; said vinyl halides are vinyl bromide and vinyl fluoride; said aromatic vinyl compounds are Alpha -methyl styrene and said fumaric acid ester is dioctyl fumarate ester.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-12-19 | 1976-06-19 | 1976-12-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-12-19 | 1980-06-19 | 1980-12-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-12-19 | 1984-06-19 | 1984-12-19 | $7700.00 | Window Closed / Lapsed |