The present invention discloses a method for preparing taurine. According to the method, ethylene oxide reacts with hydrogen sulfite to generate isethionate, after the isethionate and ammonia are subjected to an ammonolysis reaction under a microwave condition, ammonia removal is conducted to obtain a taurine salt solution, the taurine salt solution is converted into a taurine solution through acidification or ion exchange or ion membrane or heating, and taurine is extracted through concentration and crystallization. According to the present invention, the reaction time can be shortened, and the reaction temperature and pressure can be reduced, thereby achieving high yield and reducing energy consumption.

This invention relates to radiopaque polymers and to their use, particularly in the manufacture of medical devices and in methods of medical treatment, including therapeutic embolization. In particular embodiments the present disclosure relates to a hydrophilic polymer comprising pendent groups which a phenyl ring is substituted with one or more iodine groups and one or more non-iodine groups as described in more detail herein.

This invention relates to radiopaque polymers and to their use, particularly in the manufacture of medical devices and in methods of medical treatment, including therapeutic embolization. In particular embodiments the present disclosure relates to a hydrophilic polymer comprising pendent groups which a phenyl ring is substituted with one or more iodine groups and one or more non-iodine groups as described in more detail herein.

A radiation-sensitive resin composition includes: a resin including a structure unit having an acid-dissociable group; a radiation-sensitive acid generator; and a solvent. The radiation-sensitive acid generator includes at least two of compounds represented by formulae (1) to (3), provided that the compound represented by formula (1) and the compound represented by formula (3) within the scope of the compound represented by formula (2) are excluded. In the formulae (1) to (3), R.sup.1, R.sup.2 and R.sup.3 are each independently a group having a cyclic structure; X.sup.11, X.sup.12, X.sup.21, X.sup.22, X.sup.31 and X.sup.32 are each independently a hydrogen atom, a fluorine atom, or a fluorinated hydrocarbon group, provided that both X.sup.11 and X.sup.12, both X.sup.21 and X.sup.22, and both X.sup.31 and X.sup.32 are not a hydrogen atom, respectively. ##STR00001##

A radiation-sensitive resin composition includes: a resin including a structure unit having an acid-dissociable group; a radiation-sensitive acid generator; and a solvent. The radiation-sensitive acid generator includes at least two of compounds represented by formulae (1) to (3), provided that the compound represented by formula (1) and the compound represented by formula (3) within the scope of the compound represented by formula (2) are excluded. In the formulae (1) to (3), R.sup.1, R.sup.2 and R.sup.3 are each independently a group having a cyclic structure; X.sup.11, X.sup.12, X.sup.21, X.sup.22, X.sup.31 and X.sup.32 are each independently a hydrogen atom, a fluorine atom, or a fluorinated hydrocarbon group, provided that both X.sup.11 and X.sup.12, both X.sup.21 and X.sup.22, and both X.sup.31 and X.sup.32 are not a hydrogen atom, respectively. ##STR00001##

A radiation-sensitive resin composition includes: a base resin comprising a structure unit having an acid-dissociable group; and a radiation-sensitive acid generator which comprises compounds represented by formula (2) and formula (3), and optionally a compound represented by formula (1). R.sup.1-R.sup.3 are each independently a group having a cyclic structure. X.sup.11-X.sup.32 are each independently a hydrogen atom, a fluorine atom, or a fluorinated hydrocarbon group. At least one of X.sup.11 or X.sup.12, at least one of X.sup.21 or X.sup.22, and at least one of X.sup.31 or X.sup.32 are not a hydrogen atom, respectively. A.sup.11-A.sup.32 are each independently a hydrogen atom, or a hydrocarbon group having a carbon number of 1 to 20. The radiation-sensitive resin composition does not comprise a ketone-based solvent. The the radiation-sensitive resin composition does not comprise a monovalent onium cation other than an onium cation represented by formulas (X-1), (X-3), (X-4), or (X-5).

##STR00001##

A radiation-sensitive resin composition includes: a base resin comprising a structure unit having an acid-dissociable group; and a radiation-sensitive acid generator which comprises compounds represented by formula (2) and formula (3), and optionally a compound represented by formula (1). R.sup.1-R.sup.3 are each independently a group having a cyclic structure. X.sup.11-X.sup.32 are each independently a hydrogen atom, a fluorine atom, or a fluorinated hydrocarbon group. At least one of X.sup.11 or X.sup.12, at least one of X.sup.21 or X.sup.22, and at least one of X.sup.31 or X.sup.32 are not a hydrogen atom, respectively. A.sup.11-A.sup.32 are each independently a hydrogen atom, or a hydrocarbon group having a carbon number of 1 to 20. The radiation-sensitive resin composition does not comprise a ketone-based solvent. The the radiation-sensitive resin composition does not comprise a monovalent onium cation other than an onium cation represented by formulas (X-1), (X-3), (X-4), or (X-5).

##STR00001##

The present disclosure is directed to provide a process capable of producing a sulfonic acid group-containing monomer in a good yield, which can be used as a raw material of fluorine-based polymer electrolytes, such as membranes for fuel cells, catalyst binder polymers for fuel cells, and membranes for chlor-alkali electrolysis. A process for producing a sulfonic acid group-containing monomer represented by the general formula (3) includes the step of mixing and stirring a cyclic compound represented by the general formula (1) and a silanol compound represented by the general formula (2).

The present disclosure is directed to provide a process capable of producing a sulfonic acid group-containing monomer in a good yield, which can be used as a raw material of fluorine-based polymer electrolytes, such as membranes for fuel cells, catalyst binder polymers for fuel cells, and membranes for chlor-alkali electrolysis. A process for producing a sulfonic acid group-containing monomer represented by the general formula (3) includes the step of mixing and stirring a cyclic compound represented by the general formula (1) and a silanol compound represented by the general formula (2).

There is disclosed a process for producing taurine in a molar yield of at least 80% from alkali isethionate, alkali ditaurinate, or alkali tritaurinate by adding excess ammonia and at least of equal molar amount of an alkali hydroxide to a solution comprised of alkali ditaurinate, alkali tritaurinate, or their mixture and subjecting the solution to an ammonolysis to yield a solution comprised of alkali taurinate.