Superabsorbent polymers
AssigneeIndustrial Technology Research Institute
InventorsTun-Fun Way, Kelly Teng, En-Kuang Wang, Yu-Ting Chen, Jiun-Jy Chen
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Abstract
A superabsorbent polymer network formed of two monomers and two crosslinkers. The monomers and the crosslinkers are described herein. Further, a method for preparing this superabsorbent polymer network is disclosed. Also disclosed is a method of determining a ratio between two monomeric moieties in a superabsorbent polymer network formed of two monomers.
Claims20
A superabsorbent polymer network formed of 8 to 23 mole % a first monomer, 75 to 92 mole % a second monomer, 0.1 to 1 mole % a first crosslinker, and 0.2 to 1.5 mole % a second crosslinker,
- in which
- the first monomer is a C1-C10 alkene containing two or more carboxyl groups, or at least one carboxyl group and at least one amide group;
- the second monomer is a C1-C10 alkene containing only one functional group that is a carboxyl group or an amide group;
- the first crosslinker is a C1-C20 acryloyl compound containing two or more acrylamide groups, two or more acrylate groups, or at least an acrylaminde group and at least an acrylate group;
- and
- the second crosslinker is a C1-C20 hydroxyl or amine compound containing two or more hydroxyl groups, two or more amine groups, or at least one hydroxyl group and at least one amine group,
- wherein the superabsorbent polymer network contains (i) copolymers of the first monomer and the second monomer, the copolymers being bonded by both the first and the second crosslinkers;
- (ii) the copolymers and homopolymers of the first monomer, the copolymers and the homopolymers being bonded by both the first and the second crosslinkers;
- (iii) the copolymers and homopolymers of the second monomer, the copolymers and the homopolymers being bonded by both the first and the second crosslinkers;
- or (iv) the homopolymers of the first monomer and the homopolymers of the second monomer, both homopolymers being bonded by both the first and the second crosslinkers.
A process for preparing a superabsorbent polymer network, the process comprising:
- providing a mixture containing a first monomer, a second monomer, a first crosslinker, a second crosslinker, and an initiator in a solvent at 70 to 100° C. to yield crosslinked copolymers formed of the first monomer, the second monomer, and the first crosslinker;
- and
- raising the temperature of the mixture to 100 to 150° C. to induce crosslinking between the copolymers and the second crosslinker, thereby yielding the superabsorbent polymer network,
- wherein
- the first monomer, 8 to 23 mole %, is itaconic acid, fumaric acid, itaconamic acid, maleic acid, methyl maleic acid, or a combination thereof;
- the second monomer, 75 to 92 mole %, is acrylic acid, 2-hydroxyethyl methacrylate, methacrylic acid, acrylamide, methacrylamide, acryloxypropionic acid, or a combination thereof;
- the first crosslinker, 0.1 to 1 mole %, is N,N′-methylene bisacrylamide, N,N′-ethylenebisacrylamide, 1,3-propylene bisacrylamide, ethylene diacrylate, di(ethylene glycol) diacrylate, tri(ethylene glycol) diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, or a combination thereof;
- and
- the second crosslinker, 0.2 to 1.5%, is ethylene glycol, diethylene glycol, triethylene glycol, propanediol, butanediol, pentanediol, hexanediol, methylenediamine, ethylenediamine, trimethylenediamine, or a combination thereof.
A method of determining the ratio between two monomeric moieties in a superabsorbent polymer network, the method comprising:
- providing a superabsorbent polymer network formed of crosslinked copolymers, each of the copolymers prepared from a first monomer and a second monomer;
- selecting a hydrolysis condition using D2O as a solvent and D2SO4 as a catalyst, under which the copolymers are hydrolyzed to yield the first monomer and the second monomer, and the first and the second monomers thus yielded are stable;
- reacting the superabsorbent polymer network under the hydrolysis condition to yield a hydrolysis mixture of the first monomer and the second monomer;
- and
- determining a ratio of the first monomer to the second monomer in the mixture, thereby obtaining the ratio between two monomeric moieties in the superabsorbent polymer network.
Dependencies are inferred from the claim text.