US4260713A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing water-soluble polymers
Assignee: Fujifilm Wako Pure Chemical Corp
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Filing: 1979-04-09
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Granted: 1981-04-07
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Expires: 1999-04-09
Abstract
Abstract Water-soluble polymers having high molecular weight with little branching and good water solubility, particularly acrylamide series polymers having excellent flocculation effect can be obtained when 2,2'-azobis-(N,N'-dimethyleneisobutylamidine) or an acid addition salt thereof or a mixture of 2,2'-azobis(N,N'-dimethyleneisobutylamidine) or an acid addition salt thereof and another azo compound is used as polymerization initiator.
Inventors
- 👤 Motoaki Tanaka
- 👤 Tsutomu Miyagawa
- 👤 Takashi Nakata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:11
CPC Classifications
C; C08; C08F; C08F4/00; C08F4/04
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
57 words
A process for producing a water-soluble polymer which comprises polymerizing a water-soluble monomer by using as a polymerization initiator 2,2'-azobis(N,N'-dimethyleneisobutyramidine) or an acid addition salt thereof or a mixture of 2,2'-azobis(N,N'-dimethyleneisobutyramidine) or an acid addition salt thereof and another azo compound, said polymerization being initiated at an initial polymerization temperature of from 30° C. to 50° C.
Claim 2
Dependent Claim
57 words
A process for producing a water-soluble polymer which comprises polymerizing a water-soluble monomer by using as a polymerization initiator 2,2'-azobis(N,N'-dimethyleneisobutyramidine) or an acid addition salt thereof or a mixture of 2,2'-azobis(N,N'-dimethyleneisobutyramidine) or an acid addition salt thereof and another azo compound, said polymerization being initiated at an initial polymerization temperature of from 30° C. to 50° C.
Claim 3
Dependent Claim
19 words
A process according to claim 1, wherein the another azo compound is 2,2'-azobis(2-amidinopropane) or an acid addition salt thereof.
Claim 4
Dependent Claim
18 words
A process according to claim 1, wherein the another azo compound is 4,4'-azobis(4-cyanovaleric acid) or a salt thereof.
Claim 5
Dependent Claim
32 words
A process according to claim 1, wherein the water-soluble monomer is acrylic acid, methacrylic acid, acrylamide, methacrylamide, an acrylic or methacrylic aminoalcohol ester or its quaternary ammonium salt, or a mixture thereof.
Claim 6
Dependent Claim
16 words
A process according to claim 1, 2 or 3, wherein the water soluble monomer is acrylamide.
References Cited (Backward Citations)
US3428618A
Cited
US3951934A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-04-06 | 1984-10-06 | 1985-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-04-06 | 1988-10-06 | 1989-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-04-06 | 1992-10-06 | 1993-04-07 | $7700.00 | Window Closed / Lapsed |