Vinylidene fluoride-based polymer composition obtained using non-fluorinated surfactant and production method therefor

A method of producing a vinylidene fluoride-based polymer comprising emulsion polymerization of a monomer in a water-based medium in the presence of an emulsifier and an initiator without using a fluorinated surfactant,

• the monomer containing vinylidene fluoride and containing or not containing at least one selected from the group consisting of fluorine-containing alkyl vinyl compounds and compounds represented by Formula (1),
• the emulsifier being a surfactant containing a segment of polyethylene glycol and a segment of polypropylene glycol, and
• a used amount of the emulsifier being 8.5 ppm or greater and less than 100 ppm in terms of mass relative to an amount of the monomer;
• where R1 and R2 each independently are a hydrogen atom, an alkyl group having from 1 to 5 carbons, a carboxyl group, or a carboxyl group substituted with an alkyl group having from 1 to 5 carbons, R3 is a hydrogen atom or an alkyl group having from 1 to 5 carbons but R2 and R3 may be bonded to each other and form a ring, X is a single bond or an atomic group that has 1 to 20 atoms in a shortest molecular chain that links two moieties bonded to X and that has a molecular weight of 500 or less, and Y is a carboxyl group or a hydroxyl group.