EP0347241A2
Expired / Lapsed
EP
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Process for producing highly water absorptive polymer
Assignee: Mitsubishi Chemical Corp
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Filing: 1989-06-16
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Granted: —
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Expires: 2009-06-16
Abstract
Abstract A process for producing a highly water absorptive polymer, which comprises subjecting an aqueous solution of partially neutralized sodium acrylate wherein 20 to 50% or less of the carboxyl group has been neutralized to its sodium salt, the concentration of the partially neutralized sodium acrylate in the aqueous solution being 45 to 80% by weight, to solution polymerization in the presence of a crosslinking agent and optionally not exceeding 20 mol% based on the partially neutralized sodium acrylate of at least one basic vinyl monomer selected from the group consisting of (meth)acrylamide, N,N-dimethyl(meth)acrylamide, dimethylaminoethyl(meth)acrylamide, 2-vinylpyridine, and 4-vinylpyridine with the use of a water soluble radical polymerization initiator.
Inventors
- 👤 Kiichi C/O Mitsubishi Petrochem. Co. Ltd. Itoh
- 👤 Takeshi C/O Mitsubishi Petrochem. Co. Ltd Shibano
- 👤 Shuhei C/O Mitsubishi Petrochem. Co. Ltd. Yada
- 👤 Shinji C/O Mitsubishi Petrochem. Co. Ltd. Tsunoi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 00:23
CPC Classifications
C; C08; C08F; C08F220/00; C08F220/02; C08F220/04; C08F220/06; A; A61; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/60; C08F2/00; C08F2/04; C08F2/10; C08F2/44; C08F220/52; C08F220/54; C08F220/60
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
107 words
A process for producing a highly water absorptive polymer, which comprises subjecting an aqueous solution of partially neutralized sodium acrylate wherein 20 to 50% or less of the carboxyl group has been neutralized to its sodium salt, the concentration of said partially neutralized sodium acrylate in the aqueous solution being 45 to 80% by weight, to solution polymerization in the presence of a crosslinking agent and optionally not exceeding 20 mol% based on said partially neutralized sodium acrylate of at least one basic vinyl monomer selected from the group consisting of (meth)acrylamide, N,N-dimethyl(meth)acrylamide, dimethylaminoethyl(meth)acrylamide, 2-vinylpyridine, and 4-vinylpyridine with the use of a water soluble radical polymerization initiator.
Claim 2
Dependent Claim
107 words
A process for producing a highly water absorptive polymer, which comprises subjecting an aqueous solution of partially neutralized sodium acrylate wherein 20 to 50% or less of the carboxyl group has been neutralized to its sodium salt, the concentration of said partially neutralized sodium acrylate in the aqueous solution being 45 to 80% by weight, to solution polymerization in the presence of a crosslinking agent and optionally not exceeding 20 mol% based on said partially neutralized sodium acrylate of at least one basic vinyl monomer selected from the group consisting of (meth)acrylamide, N,N-dimethyl(meth)acrylamide, dimethylaminoethyl(meth)acrylamide, 2-vinylpyridine, and 4-vinylpyridine with the use of a water soluble radical polymerization initiator.
Claim 3
Dependent Claim
13 words
The process according to claim 1, wherein the basic vinyl monomer is 2-vinylpyridine.
Claim 4
Dependent Claim
40 words
The process according to claim 1 or 2, wherein the crosslinking agent is selected from the group consisting of N,N′-methylenebisacrylamide, N,N′-methylenebismethacrylamide, ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, polyethylene glycol diacrylate and polyethylene glycol dimethacrylate.
Claim 5
Dependent Claim
31 words
The process according to any one of the preceding claims, wherein the amount of the crosslinking agent used is 0.001 to 10% by weight based on the partially neutralized sodium acrylate.
Claim 6
Dependent Claim
21 words
The process according to any one of the preceding claims, wherein the water soluble radical polymerization initiator is a redox initiator.
Claim 7
Dependent Claim
34 words
The process according to any one of the preceding claims, wherein the amount of the water soluble radical polymerization initiator used is 0.001 to 10% by weight based on the partially neutralized sodium acrylate.
References Cited (Backward Citations)
No citation records indexed.
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