Polyarylene sulfide resin, method for producing same, poly(arylene sulfonium salt), and method for producing poly(arylene sulfonium salt)

A method for producing a polyarylene sulfide resin comprising a main chain including a constitutional unit represented by the following formula (1-1) or the following formula (2-1) and a terminal group bonding to a terminal of the main chain and including at least one functional group selected from the group consisting of a carboxy group, a hydroxy group and an amino group, the method comprising:

• a step of dealkylating or dearylating a poly(arylene sulfonium salt) comprising a main chain including a constitutional unit represented by the following formula (1-2) or a constitutional unit represented by the following formula (2-2) and a terminal group bonding to a terminal of the main chain and including at least one functional group selected from the group consisting of a carboxy group, a hydroxy group and an amino group:
• wherein, in formulas (1-1), (1-2), (2-1) and (2-2), R1 represents an alkyl group having 1 to 10 carbon atoms or an aryl group optionally having an alkyl group having 1 to 10 carbon atoms;
• R2b represents a direct bond, —Ar4b—, —S—Ar4b—, —O—Ar4b—, —CO—Ar4b—, —SO2—Ar4b— or —C(CF3)2—Ar4b—;
• Ar1, Ar2, Ar3b and Ar4b each independently represent an arylene group optionally having a substituent;
• Z represents a direct bond, —S—, —O—, —CO—, —SO2— or —C(CF3)2—;
• and X− represents an anion.