摘要 |
Disclosed is a method for removing a hydrocarbon solvent from a hydrocarbon solvent solution of a hydrogenated block copolymer which is obtained by hydrogenating a block copolymer comprising a polymer block composed mainly of vinyl aromatic monomer units and a polymer block composed mainly of conjugated diene monomer units, wherein the weight ratio of the vinyl aromatic monomer units to the conjugated diene monomer units is from 5/95 to 95/5, wherein the hydrogenated block copolymer has a degree of hydrogenation of 30% or more with respect to double bonds in the conjugated diene monomer units, and wherein the method comprises: (1) mixing a hydrocarbon solvent solution of the hydrogenated block copolymer with heated water to obtain a dispersion of the solution in the heated water, and (2) introducing the dispersion into a steam stripping vessel containing heated water, wherein the dispersion is spouted into the gaseous phase in the vessel toward the surface of the heated water in the vessel under conditions wherein the vapor pressure P1 of the dispersion and the pressure P2 of the gaseous phase in the vessel satisfy the formula: P1>=P2, thereby effecting a steam stripping of the dispersion to remove the solvent therefrom and obtain porous crumbs of the hydrogenated block copolymer.
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