In a method for preparing glyoxylated polyacrylamide, in which an aqueous solution of polyacrylamide is supplemented with ethanedial (glyoxal) under stirring by means of a circulation pump, the reaction is started by the addition of a base, at a basic pH value above 8, and is allowed to react under stirring and/or circulating, whereupon the reaction is stopped by the addition of an acid under stirring and/or circulating after completion of a predetermined reaction time, wherein the method is per as a discontinuous method in which the quantitative reaction of ethanedial with an excess amount of polyacrylamide in an aqueous basic medium is controlled and/or regulated by at least one, of the following factors: a) turbidity measurement b) adaptation as a function of the temperature c) pH adaptation as a function of the reaction time d) drop of pH the value, or e) current consumption of the circulation pump.

A scaffolding material for culturing a stem cell, which contains a synthetic resin, and has a storage elasticity at 100 C. of 1.010.sup.4 Pa or more and 1.010.sup.8 Pa or less, and a ratio between the storage elasticity at 25 C. and the storage elasticity at 100 C. ((storage elasticity at 25 C.)/(storage elasticity at 100 C.)) of 1.010.sup.1 or more and 1.010.sup.5 or less. The scaffolding material for stem cell culture has suitable hydrophilicity and strength, high fixation of stem cells after seeding, highly efficient cell proliferation, and excellent scratch resistance.

The present invention provides an epoxy resin composition that is provided with flexibility to combine impact resistance and mechanical strength, while maintaining epoxy resin-specific high elastic modulus, that reduces an increase in viscosity due to mixing, and that is excellent in heat resistance, storage stability, and solvent resistance. Provided is an epoxy resin composition containing: a modified polyvinyl acetal resin having a constitutional unit with an acid-modified group; a reactive diluent; and an epoxy resin, the epoxy resin composition having a sea-island phase separated structure after being cured.

The present invention provides an epoxy resin composition that is provided with flexibility to combine impact resistance and mechanical strength, while maintaining epoxy resin-specific high elastic modulus, that reduces an increase in viscosity due to mixing, and that is excellent in heat resistance, storage stability, and solvent resistance. Provided is an epoxy resin composition containing: a modified polyvinyl acetal resin having a constitutional unit with an acid-modified group; a reactive diluent; and an epoxy resin, the epoxy resin composition having a sea-island phase separated structure after being cured.

The present disclosure relates to radiopaque PVA polymers where the PVA has a first pendant group and a second pendant group, wherein the first pendant group comprises a first phenyl group bearing 1 to 5 iodine atoms, and the second pendant group comprises either (a) a second phenyl group bearing 1 to 3 substituents selected from the group W and optionally 1 to 4 iodine substituents, the group(s) W and the optional iodines being the sole substituents of the second phenyl group. Each W is selected from OH, COOH, SO.sub.3H, OPO.sub.3H.sub.2, O(C.sub.1-4alkyl), O(C.sub.1-4alkyl)OH, O(C.sub.1-4alkyl)R.sup.2, O(C.sub.2H.sub.5O).sub.qR.sup.1(CO)OC.sub.1-4alkyl and O(CO)C.sub.1-4alkyl; wherein R.sup.1 is H or C.sub.1-4 alkyl; R.sup.2 is COOH, SO.sub.3H, or OPO.sub.3H.sub.2; q is an integer from 1 to 4; wherein the group W may be in the form of a pharmaceutically acceptable salt; or (b) a pyridyl group; which is optionally in the form of a pyridinium ion.

The present disclosure relates to radiopaque PVA polymers where the PVA has a first pendant group and a second pendant group, wherein the first pendant group comprises a first phenyl group bearing 1 to 5 iodine atoms, and the second pendant group comprises either (a) a second phenyl group bearing 1 to 3 substituents selected from the group W and optionally 1 to 4 iodine substituents, the group(s) W and the optional iodines being the sole substituents of the second phenyl group. Each W is selected from OH, COOH, SO.sub.3H, OPO.sub.3H.sub.2, O(C.sub.1-4alkyl), O(C.sub.1-4alkyl)OH, O(C.sub.1-4alkyl)R.sup.2, O(C.sub.2H.sub.5O).sub.qR.sup.1(CO)OC.sub.1-4alkyl and O(CO)C.sub.1-4alkyl; wherein R.sup.1 is H or C.sub.1-4 alkyl; R.sup.2 is COOH, SO.sub.3H, or OPO.sub.3H.sub.2; q is an integer from 1 to 4; wherein the group W may be in the form of a pharmaceutically acceptable salt; or (b) a pyridyl group; which is optionally in the form of a pyridinium ion.

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.