PRODUCTION OF EPOXIDIZED DIENE BLOCK COPOLYMER

• Main Author: HARANO YOSHIYUKI
• Format: Patent
• Language: English
• Published: 22.08.2000
• Edition: 7
• Subjects: CHEMISTRY; COMPOSITIONS BASED THEREON; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP

PROBLEM TO BE SOLVED: To efficiently produce an epoxidized diene block copolymer at a low cost by dissolving a block copolymer comprising a polymer block formed from a vinylaromatic compound and a polymer block formed mainly from a conjugated diene compound or a partial hydrogenation product thereof in a solvent, dispersing the resultant solution in an aqueous solution of a surfactant, and epoxidizing by using an oxidant. SOLUTION: Ethyl acetate is used as the solvent, preferably in an amount of 10-70 wt.% of the diene block copolymer, A surfactant which forms an O/W emulsion is preferable and is contained in an amount of 0.1-10 wt.% in the aqueous solution. As the oxidizing agent, a compound such as hydrogen peroxide which directly oxidizes vinyl groups is used in the form of an aqueous solution. The aqueous oxidizing agent solution is used preferably in an amount of 50-200 pts.wt. based on 100 pts.wt. diene copolymer. Preferably, the diene copolymer has a wt. average particle size of 0. 05-10 μm.