| 摘要 |
PURPOSE: To obtain porous crumbs which absorb a softener, a plasticizer or the like within a short time, have good handleability, and can give a molded compound free from unmelted matter by steam-stripping a speficied hydrogenated block copolymer. CONSTITUTION: Porous crumbs which have a bulk density of 0.18g/cc or above, a total pore volume of 0.4cc/g or above, and a sum of the volumes of pores with pore diameters in the range of 0.14-3.9μm of 8% or above based on the total pore volume are obtained by heating to 40-150 deg.C a hydrocarbon solution having a polymer concentration of 5-60wt.% and containing a hydrogenated block copolymer obtained by hydrogenating at least 50% of the unsaturated bonds of the conjugated diene of a block copolymer composed of a block of a polymer based on a vinylaromatic compound and a block of a polymer based on a conjugated diene and having a vinylaromatic compound to conjugated diene ratio of 5-95 to 95/5 by weight, feeding the heated solution into hot water, and steam-stripping the mixture at a temperature between the boiling point of the hydrocarbon solvent or the azeotropic temperature of the hydrocarbon/ water mixture and 150 deg.C.
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