A method for producing a fluorosulfonyl group-containing compound to obtain a compound represented by the following formula 5 from a compound represented by the following formula 1 as a starting material and a method for producing a fluorosulfonyl group-containing monomer in which the fluorosulfonyl group-containing compound is used: ##STR00001##
wherein R.sup.1 and R.sup.2 are a C.sub.1-3 alkylene group, and R.sup.F1 and R.sup.F2 are a C.sub.1-3 perfluoroalkylene group.

A medical device includes: a substrate layer; an adhesive layer on at least a part of the substrate layer and containing a hydrophilic copolymer (1) containing a structural unit derived from a polymerizable monomer (A) having a sulfobetaine structure, a structural unit derived from a polymerizable monomer (B) having at least one group selected from the group consisting of a sulfonic acid group (—SO.sub.3H), a sulfuric acid group (—OSO.sub.3H), a sulfurous acid group (—OSO.sub.2H), and salt groups thereof, and a structural unit derived from a polymerizable monomer (C) having a photoreactive group; and a surface lubricious layer formed on at least a part of the adhesive layer and containing a hyaluronic acid or a salt thereof and a hydrophilic copolymer (2).

A medical device includes: a substrate layer; an adhesive layer on at least a part of the substrate layer and containing a hydrophilic copolymer (1) containing a structural unit derived from a polymerizable monomer (A) having a sulfobetaine structure, a structural unit derived from a polymerizable monomer (B) having at least one group selected from the group consisting of a sulfonic acid group (—SO.sub.3H), a sulfuric acid group (—OSO.sub.3H), a sulfurous acid group (—OSO.sub.2H), and salt groups thereof, and a structural unit derived from a polymerizable monomer (C) having a photoreactive group; and a surface lubricious layer formed on at least a part of the adhesive layer and containing a hyaluronic acid or a salt thereof and a hydrophilic copolymer (2).

A fluorosulfonyl group-containing polymer having units represented by the following formula u1, a sulfonic acid group-containing polymer having fluorosulfonyl groups in the fluorosulfonyl group-containing polymer converted into sulfonic acid groups, its production method and its applications: ##STR00001##
wherein R.sup.F1 and R.sup.F2 are a C.sub.1-3 perfluoroalkylene group.

A fluorosulfonyl group-containing polymer having units represented by the following formula u1, a sulfonic acid group-containing polymer having fluorosulfonyl groups in the fluorosulfonyl group-containing polymer converted into sulfonic acid groups, its production method and its applications: ##STR00001##
wherein R.sup.F1 and R.sup.F2 are a C.sub.1-3 perfluoroalkylene group.

A method for producing a fluorosulfonyl group-containing compound to obtain a compound represented by the following formula 5 from a compound represented by the following formula 1 as a starting material and a method for producing a fluorosulfonyl group-containing monomer in which the fluorosulfonyl group-containing compound is used:

##STR00001##

wherein R.sup.1 and R.sup.2 are a C.sub.1-3 alkylene group, and R.sup.F1 and R.sup.F2 are a C.sub.1-3 perfluoroalkylene group.

Embodiments of the present disclosure generally provide compositions and methods related to articles that display reversible photoresponsive behavior.

To provide an acid-type sulfonic acid group-containing polymer which is excellent in hydrogen gas barrier properties and hot water resistance and which generates less oligomer during production; a liquid composition and a polymer electrolyte membrane comprising this acid-type sulfonic acid group-containing polymer; and a membrane electrode assembly and a polymer electrolyte fuel cell provided with the polymer electrolyte membrane.

This acid-type sulfonic acid group-containing polymer is a polymer which has perfluoromonomer units, no monomer units having a halogen atom other than a fluorine atom, and acid-type sulfonic acid groups, and of which the hydrogen gas permeability coefficient under the conditions of a temperature of 80° C. and a relative humidity of 10%, is at most 2.5×10.sup.−9 cm.sup.3.Math.cm/(s.Math.cm.sup.2.Math.cmHg), and the mass reduction rate when being immersed in hot water at 120° C. for 24 hours is at most 15 mass %, wherein the TQ value of a polymer having fluorosulfonyl groups which is a precursor of the polymer having acid-type sulfonic acid groups, is at least 220° C.

To provide an acid-type sulfonic acid group-containing polymer which is excellent in hydrogen gas barrier properties and hot water resistance and which generates less oligomer during production; a liquid composition and a polymer electrolyte membrane comprising this acid-type sulfonic acid group-containing polymer; and a membrane electrode assembly and a polymer electrolyte fuel cell provided with the polymer electrolyte membrane.

This acid-type sulfonic acid group-containing polymer is a polymer which has perfluoromonomer units, no monomer units having a halogen atom other than a fluorine atom, and acid-type sulfonic acid groups, and of which the hydrogen gas permeability coefficient under the conditions of a temperature of 80° C. and a relative humidity of 10%, is at most 2.5×10.sup.−9 cm.sup.3.Math.cm/(s.Math.cm.sup.2.Math.cmHg), and the mass reduction rate when being immersed in hot water at 120° C. for 24 hours is at most 15 mass %, wherein the TQ value of a polymer having fluorosulfonyl groups which is a precursor of the polymer having acid-type sulfonic acid groups, is at least 220° C.

To provide a method for producing a fluorinated polymer which enables stable production of a fluorinated polymer having a high molecular weight at a high polymerization rate with good productivity and reduced environmental burdens, a method for producing a fluorinated polymer having functional groups, and a method for producing an electrolyte membrane. A method for producing a fluorinated polymer, which comprises polymerizing a monomer mixture containing tetrafluoroethylene and a fluorinated monomer having a group convertible to a sulfonic acid group or a carboxylic acid group in a polymerization medium, wherein the polymerization medium contains as the main component a C.sub.4-10 cyclic hydrofluorocarbon. Further, a method for producing a fluorinated polymer having functional groups and a method for producing an electrolyte membrane, employing the production method.