| 摘要 |
PURPOSE:To obtain a lot of spherical particles of a polyolefine resin in a short time and in one step operation by setting a stirrer on the slope of the bottom of an autoclave and by heat-treating the polyolefine resin. CONSTITUTION:A aqueous medium, a dispersing agent and resin particles are placed in an autoclave and they are stirred under heating and then cooled to obtain heat-treated resin particles. As the polyolefine resins, for example, low-density polyethylene, middle and high density polyethylene, polypropylene, ethylene-propylene copolymer and ethylene-vinyl acetate copolymer are used. A stirrer 1 is set on the slope 3 of the bottom of the autoclave 2. The liquid flow in the apparatus becomes irregular by this means and horizontal and perpendicular flows are mixed to bring about so-called a turbulent flow, which prevent the crowding of polydefine resin particles at upper layer, which causes agglutination and agglomeration of the particles. A turbine type stirrer 1 which consists of an umbrella-shaped round plate 4 and shuttlecock plates 5, 5... set radially on the round plate is most preferable. |
