US4777232A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing polysaccharide graft polymers which absorb water and are capable of swelling
Assignee: Huels AG
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Filing: 1987-02-13
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Granted: 1988-10-11
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Expires: 2007-02-13
Abstract
Abstract The invention relates to a single-stage method of producing polysaccharide g FD-water/g polymers. Fine particulate graft polymers with very high water absorption capacity can be prepared by employing a nonionic lipophilic surface active agent and a nonionic hydrophilic surface active agent.
Inventors
- 👤 Klaus Heidel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 12:45
CPC Classifications
C; C08; C08F; C08F251/00; A; A61; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/60
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
103 words
A method of manufacturing a graft polymer which is in particle form and which swells substantially when exposed to water, comprising polymerizing a dispersion comprising: (i) an aliphatic hydrocarbon; (ii) an aqueous solution of at least one water-soluble unsaturated monomer; (iii) a polysaccharide; and (iv) a combination of (a) a nonionic, water-insoluble surface active agent which is at least partially soluble in said aliphatic hydrocarbon and which has an HLB value less than 10; and (b) a nonionic, water-soluble polyethylene-glycol-group-containing surface active agent with an HLB value greater than 10; wherein said polymerizing step is carried out as a single-stage batch radical polymerization.
Claim 2
Independent Claim
103 words
A method of manufacturing a graft polymer which is in particle form and which swells substantially when exposed to water, comprising polymerizing a dispersion comprising: (i) an aliphatic hydrocarbon; (ii) an aqueous solution of at least one water-soluble unsaturated monomer; (iii) a polysaccharide; and (iv) a combination of (a) a nonionic, water-insoluble surface active agent which is at least partially soluble in said aliphatic hydrocarbon and which has an HLB value less than 10; and (b) a nonionic, water-soluble polyethylene-glycol-group-containing surface active agent with an HLB value greater than 10; wherein said polymerizing step is carried out as a single-stage batch radical polymerization.
Claim 3
Dependent Claim
17 words
The method of claim 1, wherein said polymerizing is carried out at temperatures between about 40°-100° C.
Claim 4
Dependent Claim
37 words
The method of claim 1, wherein said polymerizing is carried out in the presence of a surface active agent with an HLB value of 5-10 and a polyethylene-glycol-group-containing surface active agent with an HLB value of 12-20.
Claim 5
Dependent Claim
20 words
The method of claim 1, wherein said graft polymer comprises 10-70 wt. % polysaccharide and 90-30 wt. % unsaturated monomer.
Claim 6
Dependent Claim
24 words
The method of claim 4, wherein said graft polymer comprises 30-50 wt. % of said polysaccharide and 70-50 wt. % of said unsaturated monomer.
Claim 7
Dependent Claim
10 words
The method of claim 1, wherein said polysaccharide is starch.
Claim 8
Dependent Claim
37 words
The method of claim 1, wherein said water soluble unsaturated monomer is (meth)acrylic acid, and wherein prior to said polymerizing, said methacrylic acid is neutralized to the extent of 50-95% in the presence of an aliphatic hydrocarbon.
Claim 9
Dependent Claim
29 words
The method of claim 1, wherein said water insoluble surface active agent is a sorbitan ester and said water soluble surface active agent is an alkoxyethylate or polyethylene glycol.
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) | 1991-10-11 | 1992-04-11 | 1992-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-11 | 1996-04-11 | 1996-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-11 | 2000-04-11 | 2000-10-11 | $7700.00 | Window Closed / Lapsed |