A process for producing an epoxidized diene polymer includes: dispersing or suspending
a diene polymer (C) having a ball-reduced particle size of 0.05-20 mm in a medium
(A) in the presence of powder particles (B) insoluble in the medium (A), or in
an aqueous medium in the presence of a phenol-based stabilizer and/or a phosphorus-based
stabilizer; and epoxidizing the diene polymer (C) by an epoxidizing agent, therefore,
problems associated with epoxidation performed by dissolving diene polymer in a
solvent are eliminated; an economical method for epoxidizing, producing, and purifying
a diene polymer (C) in a solid form is provided; and the epoxidized diene polymer
having an excellent heat stability can be obtained.
