Patent US3614198A successfully refreshed from Google Patents.
EP0233014A2
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Polymers and processes for their production from water soluble monomers
Assignee: Ciba Specialty Chemicals Water Treatments Ltd
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Filing: 1987-01-29
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Granted: —
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Expires: 2007-01-29
Abstract
Abstract Water soluble or water swellable polymeric material is made by forming a dispersion in a non-aqueous liquid of water absorbent seed particles formed from first monomer, absorbing an aqueous solution of water soluble ethylenically unsaturated second monomer into the particles and polymerising the second monomer to form the said polymeric material. The invention is of particular value in the production of irregularly shaped non-spheroidal highly absorbent polymeric particles suitable for use in diapers, or for the production of soluble polymers.
Inventors
- 👤 Peter Flesher
- 👤 David Farrar
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-25 06:02
CPC Classifications
C; C08; C08F; C08F265/00; C08F265/02; A; A61; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/60; C08F291/00
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
80 words
A process for making water soluble or water swellable polymeric material comprising forming a dispersion in non-aqueous liquid of water absorbent seed particles formed from first monomer, absorbing an aqueous solution of water soluble ethylenically unsaturated second monomer into the particles and polymerising the second monomer to form the said polymeric material, and in which the polymeric material produced by the polymerisation in the non-aqueous liquid is in the form of particles having an average dry size of above l00µm.
Claim 2
Dependent Claim
80 words
A process for making water soluble or water swellable polymeric material comprising forming a dispersion in non-aqueous liquid of water absorbent seed particles formed from first monomer, absorbing an aqueous solution of water soluble ethylenically unsaturated second monomer into the particles and polymerising the second monomer to form the said polymeric material, and in which the polymeric material produced by the polymerisation in the non-aqueous liquid is in the form of particles having an average dry size of above l00µm.
Claim 3
Dependent Claim
37 words
A process according to claim l in which the first monomer is water soluble ethylenically unsaturated monomer of which at least 50% by weight is substantially identical to at least 50% by weight of the second monomer.
Claim 4
Dependent Claim
17 words
A process according to claim l in which the seed particles are irregularly shaped, crushed, gel particles.
Claim 5
Dependent Claim
18 words
A process according to claim l or claim 2 in which the polymeric material is dried and crushed.
Claim 6
Dependent Claim
21 words
A process according to any preceding claim in which the seed particles hve a dry average size of at least 50µm.
Claim 7
Dependent Claim
48 words
A process according to any preceding claim in which the polymeric material is water insoluble but water swellable and is produced in the non-aqueous liquid wholly or mainly in the form of agglomerates or of irregularly shaped non-spherical particles which are dried and separated from the non-aqueous liquid.
Claim 8
Dependent Claim
31 words
A process according to claim 6 in which the first and second monomers each comprise 50 to l00% acrylic acid or a salt thereof and 0 to 50% by weight acrylamide.
Claim 9
Dependent Claim
28 words
A process according to claim 6 in which the first and second monomers are each selected from acrylic acid and ammonium and alkali metal salts of acrylic acid.
Claim 10
Dependent Claim
22 words
A process according to any of claims 6 to 8 in which the first and second monomers each include cross linking agent.
Claim 11
Dependent Claim
23 words
l0. A process according to any of claims 6 to 8 in which the seed particles have a hydrophobic coating that reduces absorption.
Claim 12
Dependent Claim
19 words
A process according to any of claims l to 5 in which the polymeric material is soluble in water.
Claim 13
Dependent Claim
28 words
A process according to claim ll in which the polymer of the seed particles and/or the polymer formed from the second monomer has molecular weight below l million.
Claim 14
Dependent Claim
92 words
A process according to claim ll in which the polymer of the seed particles and the polymer formed from the second monomer has molecular weight below l million and the first and second monomers each comprise at least 20% by weight water soluble ethylenically unsaturated ionic monomer and the ionic monomer in each is substantially the same and is selected from diallyldimethyl ammonium chloride, dialkylaminoalkyl (meth) -acrylate or -acrylamide or a salt thereof, ethylenically unsaturated carboxylic acids and water soluble salts thereof and ethylenically unsaturated sulphonic acids and water soluble salts thereof.
Claim 15
Dependent Claim
29 words
A process according to claim l3 in which the first and second monomers each consist of 50 to l00% by weight diallyldimethyl ammonium chloride and 0 to 50% acrylamide.
Claim 16
Dependent Claim
63 words
A process according to claim ll or claim l2 in which the seed polymer is a cationic polymer selected from polyethylene imine, polyamine epichlorhydrin reaction products and polymers of cationic ethylenically unsaturated monomers and the second monomers are selected from cationic ethylenically unsaturated monomers, wherein the cationic ethylenically unsaturated monomers are selected from diallyldimethyl ammonium chloride and dialkylaminoalkyl (meth) acrylates and salts thereof.
Claim 17
Dependent Claim
19 words
A process according to claim l5 in which the seed polymer has a molecular weight of below l million.
Claim 18
Dependent Claim
14 words
A aqueous solution of a polymer according to any of claims ll to l5.
Claim 19
Dependent Claim
48 words
An absorbent article comprising an absorbent fibrous body in which water absorbent particles are physically trapped, characterised in that the particles are in the form of agglomerates or of irregularly shaped non-spheroidal particles and have been made by a process according to any of claims 6 to l0.
References Cited (Backward Citations)
No citation records indexed.
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