Fluorine-containing polymer, mold release agent composition and mold release method

A fluorine-containing polymer having repeating units derived from:

• (a) a fluorine-containing monomer having a perfluoroalkyl group,
• (b) a fluorine-free monomer having a hydrocarbon group, and
• (c) a fluorine-free monomer having a phosphate group,
• wherein
• the fluorine-containing monomer (a) is a compound represented by formula:
• CH2═C(—X11)—C(═O)—Y11—Y12—Rf,
• wherein
• X11 is a hydrogen atom, or a methyl group,
• Y11 is —O— or —NH—,
• Y12 is a direct bond, a divalent aliphatic hydrocarbon group, a divalent aromatic hydrocarbon group, or a divalent cycloaliphatic hydrocarbon group, and
• Rf is a perfluoroalkyl group having 6 to 20 carbon atoms,
• wherein the hydrocarbon group in the hydrocarbon group-containing fluorine-free monomer (b) has 1 to 40 carbon atoms,
• wherein an amount of the fluorine-containing monomer (a) is 35 to 80% by weight, based on the fluorine-containing polymer,
• wherein an amount of the hydrocarbon group-containing fluorine-free monomer (b) is 15 to 50% by weight, based on the fluorine-containing polymer,
• wherein an amount of the phosphate group-containing fluorine-free monomer (c) is 0.1 to 4% by weight, based on the fluorine-containing polymer,
• wherein the fluorine-containing polymer does not comprise a repeating unit derived from a silicon-containing monomer, and
• wherein a chain transfer agent is not used in the production of the fluorine-containing polymer.