Method of preparing polymer compound

A method for preparing a polymer compound, comprising :

• copolymerizing a monomer (m01) represented by general formula (m0-1) andamonomer (m02) representedbygeneral formula (m0-2) to obtain a first polymer compound;
• and
• causing the first polymer compound and an acid component to react with each other to obtain a second polymer compound represented by general formula (p0):
• wherein R1 is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, Va01 is a divalent hydrocarbon group which may have an ether bond, na01is an integer of 0 to 2, Ra10 is a tertiary alkyl ester-type acid dissociable group, R2 is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, Va02 is a divalent linking group containing a heteroatom, or a single bond, Ra07 is a monovalent organic group, naul is an integer of 0 to 3, Ra20 is an acid dissociable group, na022 is an integer of 1 to 3, and u1, u2, and u3 each independently represent a ratio with respect to all the structural units constituting the second polymer compound and each are a positive number.