Hygroscopic hydrogels including a cross-linked polymer, the polymer being prepared by polymerization of one or more monomers, wherein at least one of the monomers is a compound of formula I, are provided. Related monomers and polymers, as well as methods for the production and use thereof, are also provided. Hygroscopic hydrogels as described herein may be used for water harvesting, for example. (I) (formula I)

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A gas-absorbing material that contains amino group-having polymer compound particles and fine particles having a primary particle diameter of 1000 nm or less is a gas-absorbing material having a markedly higher gas absorption/desorption speed. Here, as the polymer compound of the amino group-having polymer compound particles, for example, a (meth)acrylamide polymer can be used, and as the fine particles, for example, water-repellent inorganic particles or fluororesin particles can be used.

A gas-absorbing material that contains amino group-having polymer compound particles and fine particles having a primary particle diameter of 1000 nm or less is a gas-absorbing material having a markedly higher gas absorption/desorption speed. Here, as the polymer compound of the amino group-having polymer compound particles, for example, a (meth)acrylamide polymer can be used, and as the fine particles, for example, water-repellent inorganic particles or fluororesin particles can be used.

A polymer compound is provided which is changed from a water-insoluble state to a water-soluble state by irradiation with light. The polymer compound is represented by Formula (5), where A and B are a single bond or a functional group, R.sup.3, R.sup.4, and R.sup.9 are hydrogen or an alkyl group, and R.sup.6 and R.sup.7 are hydrogen, an alkyl group, or the like.

A method of manufacturing a polymerizable composition is capable of imparting antibacterial properties and the like to a cured product of polymerizable composition without deteriorating an appearance of the cured product of the polymerizable composition. The method of manufacturing a polymerizable monomer wherein a solution, that a second polymerizable monomer is dissolved in a first solvent, is dispersed in a first polymerizable monomer, includes mixing the first polymerizable monomer, the second polymerizable monomer, and the first solvent. The first polymerizable monomer is a liquid, and the second polymerizable monomer is a solid.

A method of manufacturing a polymerizable composition is capable of imparting antibacterial properties and the like to a cured product of polymerizable composition without deteriorating an appearance of the cured product of the polymerizable composition. The method of manufacturing a polymerizable monomer wherein a solution, that a second polymerizable monomer is dissolved in a first solvent, is dispersed in a first polymerizable monomer, includes mixing the first polymerizable monomer, the second polymerizable monomer, and the first solvent. The first polymerizable monomer is a liquid, and the second polymerizable monomer is a solid.

Copolymers prepared by the free-radical copolymerization of the following components: a) cationic monomers selected from the group consisting of cationic (meth)acrylamide monomers and diallyldimethylammonium chloride, b) polyethylene glycol macromonomers, and c) uncharged acrylamide monomers.

Copolymers prepared by the free-radical copolymerization of the following components: a) cationic monomers selected from the group consisting of cationic (meth)acrylamide monomers and diallyldimethylammonium chloride, b) polyethylene glycol macromonomers, and c) uncharged acrylamide monomers.

Copolymers prepared by the free-radical copolymerization of the following components: a) cationic monomers selected from the group consisting of cationic (meth)acrylamide monomers and diallyldimethylammonium chloride, b) polyethylene glycol macromonomers, and c) uncharged acrylamide monomers.

This invention concerns a transparent composition comprising at least a first amphoteric water-soluble polymer, which comprises: A units of a cationic monomer selected from: acidified or quaternised dimethylaminoethyl acrylate salts, acidified or quaternised dimethylaminoethyl methacrylate salts, acidified or quaternised dimethylaminopropyl acrylamide salts, and acidified or quaternised dimethylaminopropyl methacrylamide salts, and mixtures thereof; B units of 2-acrylamido-2-methylpropanesulphonic acid and/or salts thereof; and optionally C units of acrylamide,

characterised in that the molar ratio between the A units of cationic monomer and the B units of 2-acrylamido-2-methylpropanesulphonic acid and/or salts thereof is between 0.4 and 1.4.