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US4420588A Expired / Lapsed US ⏱️ 0.0 years remaining

Water-absorbing rubber composition

Assignee: Kuraray Co Ltd
•
Filing: 1981-12-10
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Granted: 1983-12-13
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Expires: 2001-12-10
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Abstract

Abstract A water-absorbing rubber composition comprising (A) a 1,3-diene rubber with a crystal or glass region content as measured at an ordinary temperature of 5-50% and (B) a highly water-absorbing resin dispersed in the said rubber, the said highly water-absorbing resin being a product of crosslinking of a polymer which contains as monomer component thereof at least 40 mole percent of an alpha , beta -unsaturated compound containing 1 or 2 groups each selected from the class consisting of a carboxyl group and a group convertible to a carboxyl group with at least one crosslinking agent selected from the class consisting of a polyfunctional epoxy compound and a polyamine, the resin being in the form of a powder capable of passing through a 20-mesh Tyler screen and absorbing 20-500 times its own weight of distilled water. The composition can absorb water rapidly and produce a high swelling pressure, and has good durability in the swollen state.

Inventors

  • 👤 Yoshihiro Yoshioka
  • 👤 Hiroshi Harima

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 09:31
CPC Classifications
C; C09; C09K; C09K3/00; C09K3/10; C08; C08L; C08L21/00; C09K2003/1034; C09K2003/1046; C09K2200/00; C09K2200/06; C09K2200/0607; C09K2200/0645

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 207 words
A water-absorbing rubber composition comprising (A) a 1,3-diene rubber with a crystal or glass region content of 5-50% when measured at about 25° C. having molecular weight of 50,000 to 1,000,000 and a melting point of the crystal regions of 20°-90° C., and (B) a highly water-absorbing resin dispersed in said rubber, the ratio of mixing said 1,3-diene rubber to said water-absorbing resin ranging from 10-300 parts by weight of resin per 100 parts by weight of said rubber, said resin being a product of crosslinking of a polymer which contains as a monomer at least 40 mole percent of an α,β-unsaturated compound containing 1 or 2 groups each selected from the class consisting of a carboxyl group and a group convertible to a carboxyl group with at least one crosslinking agent selected from the group consisting of a polyfunctional epoxy compound containing at least two epoxy groups and a polyamine having a molecular weight or 60-5000 and represented by a general formula H--(NH--CH 2 --CH 2 --) n NH 2 wherein n is an integer of 1 to 110, said resin being in the form of a powder capable of passing through a 20-mesh Tyler screen and absorbing 20-500 times its own weight of distilled water.
Claim 2
Dependent Claim 207 words
A water-absorbing rubber composition comprising (A) a 1,3-diene rubber with a crystal or glass region content of 5-50% when measured at about 25° C. having molecular weight of 50,000 to 1,000,000 and a melting point of the crystal regions of 20°-90° C., and (B) a highly water-absorbing resin dispersed in said rubber, the ratio of mixing said 1,3-diene rubber to said water-absorbing resin ranging from 10-300 parts by weight of resin per 100 parts by weight of said rubber, said resin being a product of crosslinking of a polymer which contains as a monomer at least 40 mole percent of an α,β-unsaturated compound containing 1 or 2 groups each selected from the class consisting of a carboxyl group and a group convertible to a carboxyl group with at least one crosslinking agent selected from the group consisting of a polyfunctional epoxy compound containing at least two epoxy groups and a polyamine having a molecular weight or 60-5000 and represented by a general formula H--(NH--CH 2 --CH 2 --) n NH 2 wherein n is an integer of 1 to 110, said resin being in the form of a powder capable of passing through a 20-mesh Tyler screen and absorbing 20-500 times its own weight of distilled water.
Claim 3
Dependent Claim 27 words
The water-absorbing rubber composition of claim 1, wherein said 1,3-diene rubber with a crystal region content as measured at an ordinary temperature of 5-50% is chloroprene rubber.
Claim 4
Dependent Claim 24 words
The water-absorbing rubber composition of claim 2, wherein said chloroprene rubber has a crystal region content as measured at an ordinary temperature of 15-35%.
Claim 5
Dependent Claim 76 words
The composition of claim 1, wherein said 1,3-diene rubber is a block copolymer of the type A-B-A wherein A is a polymer segment composed of a monovinyl-substituted aromatic compound having a glass transition temperature of at least 70° C. and a degree of polymerization of 10-2,500 and B is a noncrystalline polymer segment composed of a 1,3-diene having a degree of polymerization of 500-15,000, and said A segments amounting to 5-50% of the whole rubber component.
Claim 6
Dependent Claim 28 words
The water-absorbing rubber composition of claim 1, wherein the highly water-absorbing resin is a polyfunctional epoxy compound-crosslinked reaction product of a maleic anhydride-containing copolymer and a basic substance.
Claim 7
Dependent Claim 17 words
The water-absorbing rubber composition of claim 5, wherein the maleic anhydride-containing copolymer is an alpha-olefin-maleic anhydride copolymer.
Claim 8
Dependent Claim 21 words
The water-absorbing rubber composition of claim 6, wherein the alpha-olefin-maleic anhydride copolymer is an alternating compolymer of isobutylene and maleic anhydride.
Claim 9
Dependent Claim 43 words
The water-absorbing rubber composition of claim 5, wherein the maleic anhydride-containing copolymer is a copolymer of maleic anhydride and at least one comonomer selected from the group consisting of styrene, vinyl acetate, methyl vinyl ether, acrylic acid ester, methacrylic acid ester and acrylonitrile.
Claim 10
Dependent Claim 27 words
The composition of claim 1, wherein said resin is a polyamine crossslinked reaction product of a maleic anhydride-containing copolymer and a basic substance making it more hydrophilic.
Claim 11
Dependent Claim 15 words
The composition of claim 9, wherein said maleic anhydride-containing copolymer is an alphaolefin-maleic anhydride copolymer.
Claim 12
Dependent Claim 19 words
The composition of claim 10, wherein said alpha-olefin-maleic anhydride copolymer is an alternating copolymer of isobutylene and maleic anhydride.
Claim 13
Dependent Claim 43 words
The water-absorbing rubber composition of claim 9, wherein the maleic anhydride-containing copolymer is a copolymer of maleic anhydride and at least one comonomer selected from the group consisting of styrene, vinyl acetate, methyl vinyl ether, acrylic acid ester, methacrylic acid ester and acrylonitrile.
Claim 14
Dependent Claim 39 words
The water-absorbing rubber composition of claim 1, wherein the highly water-absorbing resin is a polyacrylic acid alkali metal salt crosslinked with at least one crosslinking agent selected from the group consisting of a polyfunctional epoxy compound and a polyamine.
Claim 15
Dependent Claim 17 words
The water-absorbing rubber composition of claim 1, wherein the polyfunctional epoxy compound is a glycerol diglycidyl ether.
Claim 16
Dependent Claim 19 words
The composition of claim 1, wherein said polyamine is polyethyleneimine having a molecular weight of not more than 5,000.
Claim 17
Dependent Claim 18 words
The composition of claim 1, wherein said resin can absorb 50-300 times its own weight of distilled water.
Claim 18
Dependent Claim 42 words
The composition of claim 1, wherein the amount of said resin (B) is 10-300 parts by weight per 100 parts by weight of the 1,3-diene rubber (A) with a crystal or glass region content of 5-50% when measured at about 25° C.
Claim 19
Dependent Claim 13 words
A water leak stopper predominantly composed of water-absorbing rubber composition of claim 1.

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) 1986-12-12 1987-06-13 1987-12-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-12-12 1991-06-13 1991-12-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-12-12 1995-06-13 1995-12-13 $7700.00 Window Closed / Lapsed

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