Fluororesin, fluororesin particles, and methods for producing these

A method for producing a fluororesin, comprising:

• polymerizing a monomer of the following formula (3) in a presence of a radical polymerization initiator and a chain transfer agent, thereby obtaining a fluororesin that comprises a residue unit of the following formula (4),
• wherein the chain transfer agent comprises an organic compound having 1 to 20 carbon atoms and including at least one atom selected from the group consisting of a hydrogen atom and a chlorine atom, and
• the fluororesin has a weight average molecular weight Mw of from 5×104 to 3×105 and has a yellow index of 6 or less when formed into a molded product in a thickness of 3 mm after heat-melting for 24 h at 280° C.,
• wherein Rf5, Rf6, Rf7, and Rf8 are each independently selected from the group consisting of a fluorine atom, a linear perfluoroalkyl group having 1 to 7 carbon atoms, a branched perfluoroalkyl group having 3 to 7 carbon atoms, or a cyclic perfluoroalkyl group having 3 to 7 carbon atoms;
• the linear or branched perfluoroalkyl group optionally have an ethereal oxygen atom;
• Rf5, Rf6, Rf7, and Rf8 may be linked to one another to form a ring having 4 to 8 carbon atoms;
• and the ring optionally includes an ethereal oxygen atom.