| 摘要 |
PURPOSE:To obtain the title fine powder in a short time in high efficiency at a low cost, by emulsifying a solution of a thermoplastic polymer in the form of an O/W-type emulsion, evaporating the organic solvent under agitation and separating the powder from the emulsion. CONSTITUTION:(A) A thermoplastic polymer is dissolved in (B) an organic solvent to obtain a polymer solution. (C) Water containing an emulsifier is added to the solution under agitation to form an O/W-type emulsion via a W/O-type emulsion. The component B is evaporated from the resultant emulsion under agitation and the objective fine powder is separated from the emulsion. The component B is preferably a solvent having a boiling point of <100 deg.C and essentially hardly soluble or insoluble in water (e.g., benzene). The compo nent C is preferably a protective colloid substance (e.g., polyvinyl alcohol) and the component A is preferably selected from aromatic polysulfone resin, amor phous nylon and amorphous polyarylate and the polymer solution preferably contains a thermosetting resin. |
