To provide a method for fractionating a liquid composition, which is excellent in separability of the liquid composition. This method for fractionating a liquid composition comprises discharging, from a discharge port of a filling nozzle, a liquid composition containing a solvent and a polymer having ion exchange groups, and fractionating a predetermined amount of the liquid composition, characterized in that the temperature of the liquid composition is controlled so that the average tan 1 of the liquid composition when discharged from the discharge port of the filling nozzle becomes to be at most 1.00.

An object of the present invention is to provide a modified vinyl alcohol polymer having a sulfonic acid or a salt thereof, the polymer having notably improved water solubility as compared with a pre-modified vinyl alcohol polymer. A modified vinyl alcohol polymer (A) has in a side chain thereof a sulfonic acid group or a salt thereof, and in the modified vinyl alcohol polymer (A), a degree of modification with the sulfonic acid group or the salt thereof is 0.01 mol % or more and 10 mol % or less, and a block character of residual vinyl ester units is 0.55 or more and 1 or less.

An object of the present invention is to provide a modified vinyl alcohol polymer having a sulfonic acid or a salt thereof, the polymer having notably improved water solubility as compared with a pre-modified vinyl alcohol polymer. A modified vinyl alcohol polymer (A) has in a side chain thereof a sulfonic acid group or a salt thereof, and in the modified vinyl alcohol polymer (A), a degree of modification with the sulfonic acid group or the salt thereof is 0.01 mol % or more and 10 mol % or less, and a block character of residual vinyl ester units is 0.55 or more and 1 or less.

A scaffolding material for culturing a cell, the scaffolding material for culturing a cell containing a synthetic resin, and having a nitrogen content of the synthetic resin of 0.1% by mass or more and 10% by mass or less. According to the scaffolding material for cell culture, the scaffolding material can have suitable hydrophilicity and strength, high fixation of cells after seeding, and highly efficient cell proliferation.

A scaffolding material for culturing a cell, the scaffolding material for culturing a cell containing a synthetic resin, and having a nitrogen content of the synthetic resin of 0.1% by mass or more and 10% by mass or less. According to the scaffolding material for cell culture, the scaffolding material can have suitable hydrophilicity and strength, high fixation of cells after seeding, and highly efficient cell proliferation.

The present invention provides an aqueous emulsion composition excellent in heat resistance, water resistance, hot water resistance, boiling water resistance, and viscosity stability and also excellent in stain resistance. The present invention relates to an aqueous emulsion composition including an aqueous emulsion (D) and a cyclic acid anhydride (E). The aqueous emulsion (D) includes a polymer (X) having an ethylenically unsaturated monomer (B), a polyvinyl alcohol resin (A), and water. At least one selected from the polyvinyl alcohol resin (A) and the polymer (X) has, in a main chain thereof, a structural unit derived from a monomer (C) represented by the following formula (I), (II), (III), or (IV). ##STR00001## (The definitions of the symbols in the formulae are omitted.)

The present invention provides an aqueous emulsion composition excellent in heat resistance, water resistance, hot water resistance, boiling water resistance, and viscosity stability and also excellent in stain resistance. The present invention relates to an aqueous emulsion composition including an aqueous emulsion (D) and a cyclic acid anhydride (E). The aqueous emulsion (D) includes a polymer (X) having an ethylenically unsaturated monomer (B), a polyvinyl alcohol resin (A), and water. At least one selected from the polyvinyl alcohol resin (A) and the polymer (X) has, in a main chain thereof, a structural unit derived from a monomer (C) represented by the following formula (I), (II), (III), or (IV). ##STR00001## (The definitions of the symbols in the formulae are omitted.)

The invention is related to a class of hydrophilic copolymers comprising loosely dangling thiol-containing pendant groups. The hydrophilic copolymers are highly reactive towards azetidinium groups of an azetidinium-containing polymer upon heating and can find particular use in for producing water-soluble highly-branched hydrophilic polymeric material useful for producing water gradient contact lenses.

The invention is related to a class of hydrophilic copolymers comprising loosely dangling thiol-containing pendant groups. The hydrophilic copolymers are highly reactive towards azetidinium groups of an azetidinium-containing polymer upon heating and can find particular use in for producing water-soluble highly-branched hydrophilic polymeric material useful for producing water gradient contact lenses.

A water-absorbent resin containing a vinyl alcohol-based polymer and having a crystal melting enthalpy of more than 0 J/g in a dry state.