 Protective head shield |
| What is claimed is: 1. A head shield for protection of the face and clothing during application of ... |
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| Composite material having absorbable and non-absorbable components for use with mammalian tissue |
| I claim: 1. A composite material for use with mammalian tissue consisting essentially of: (a) an ... |
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| Shoulder restraint |
| OF THE PREFERRED EMBODIMENT Referring now to the drawings, and in particular FIG. 1, the apparatus ... |
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| Packaged catheter arrangement |
| We claim: 1. A packaged catheter arrangement, comprising a flexible rubber catheter having an ... |
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| Bag with easy open line of perforations |
| The invention comprises a gusseted bag having one end folded over along a fold line to form a ... |
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| Tampon system and method |
| As will be appreciated, the system of this invention provides a sanitary package and permits ... |
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| Impact resistant thermoplastic resin composition |
| We claim: 1. An impact resistant thermoplastic resin composition comprising a graft copolymer II ... |
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| Urinary catheter package |
| The general purpose of the present invention is to disclose a unitary and compact package for an ... |
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| Prefilled catheter tip syringe kit |
| It has not been discovered that an improved medical procedure may be employed for the irrigation of ... |
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| Method for making splittable catheter |
| OF THE DRAWINGS In FIG. 1, a cross sectional view has been taken as would be seen from the plane ... |
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Hydrogel composites and superporous hydrogel composites having fast swelling, high mechanical strength, and superabsorbent properties
| Details |
Inventors: Park, Kinam; Chen, Jun; Park, Haesun;
Assignee: Purdue Research Foundation (West Lafayette, IN)
Primary Examiner: Cooney, Jr.; John M.
Assistant Examiner:
Attorney, Agent or Firm: Meadows; James H.
A superporous hydrogel composite is formed by polymerizing one or more ethylenically-unsaturated monomers, and a multiolefinic crosslinking agent, in the presence of particles of a disintegrant and a blowing agent. The disintegrant, which rapidly absorbs water, serves to greatly increase the mechanical strength of the superporous hydrogel and significantly shorten the time required to absorb water and swell. Superporous hydrogel composites prepared by this method have an average pore size in the range of 10 .mu.m to 3,000 .mu.m. Preferred particles of disintegrant include natural and synthetic charged polymers, such as crosslinked sodium carboxymethylcellulose, crosslinked sodium starch glycolate, and crosslinked polyvinylpyrrolidone. The blowing agent is preferably a compound that releases gas bubbles upon acidification, such as NaHCO.sub.3. Improved hydrogel composites formed without a blowing agent are also provided. |
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DETAILED DESCRIPTION The present invention is for a superporous hydrogel (SPH) composite, and related hydrogel composite, formed of an interpenetrating network of a polymer and particles of a fast water-absorbing material (a disintegrant), as defined hereinbelow.
The polymer is formed of at least one ethylenically-unsaturated monomer and a multi olefinic crosslinking agent, and the polymer is further crosslinked to the disintegrant particles.
A superporous hydrogel composite of the invention is characterized by having superabsorbence properties and mechanical strength, as exemplified by its swelling ratio and compression modulus, respectively.
The SPH composite also has a very short swelling time.
A superporous hydrogel composite of the present invention has an average pore size in the range of 10 .
mu.
m-3,000 .
mu.
m, more preferably 50 .
mu.
m-1,000 .
mu.
m, and most preferably 100 .
mu.
m-600 .
mu.
m.
A superporous hydrogel composite of the present invention is formed in part from at least one ethylenically-unsaturated monomer.
The monomer is preferably selected from (meth)acrylic acid, salts of (meth)acrylic acid, esters of (meth)acrylic acid, salts and acids of esters of (meth)acrylic acid, amides of (meth)acrylic acid, N-alkyl amides of (meth)acrylic acid, salts and acids of N-alkyl amides of (meth)acrylic acid, N-vinyl pyrrolidinone, acrylamide, acrylamide derivatives (e.
g.
, N-n-propylacrylamide, N-isopropylacrylamide), methacrylamide, methacrylamide derivatives (e.
g.
, N-cyclopropylmethacrylamide), and the like, and mixtures thereof.
The superporous hydrogel composite is also formed from a crosslinking agent, which is preferably selected from BIS (N,N'-methylenebisacrylamide), ethylene glycol di(meth)acrylate, piperazine diacrylamide, glutaraldehyde, epichlorohydrin, and degradable crosslinking agents including crosslinkers containing 1,2-diol structures (e.
g.
, N,N'-diallyltartardiamide), and functionalized peptides and proteins (e.
g.
, albumin modified with vinyl groups).
A superporous hydrogel composite of the invention further is formed of particles of a disintegrant, as defined hereinbelow
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Obesity Surgery 
