METHOD FOR REMOVING HYDROCARBON SOLVENT FROM SOLUTION OF HYDROGENATED BLOCK COPOLYMER IN HYDROCARBON SOLVENT

摘要

A method for removing a solvent from a hydrocarbon solvent solution of a hydrogenated block copolymer (a hydrogenation degree for double bonds of conjugated diene monomer units: 30 % or more) obtained by hydrogenating a block copolymer comprising a polymer block containing a vinyl aromatic monomer unit as a main component and a polymer block containing a conjugated diene monomer unit as another main component (vinyl aromatic monomer unit/ conjugated diene monomer unit, in weight ratio: 5/95 to 95/5), characterized as comprising (1) admixing the hydrocarbon solvent solution of a hydrogenated block copolymer with hot water to produce a dispersion comprising the solution dispersed in the hot water, and (2) introducing the dispersion to a steam stripping vessel by spraying the dispersion toward the surface of the hot water under a condition wherein the vapor pressure P1 of the dispersion and the pressure P2 of the gas phase satisfy the relationship: P1 >/= P2 , to remove the solvent through steam stripping, thereby preparing a porous crumb.