Abstract: Provided is a method for preparing an oligomer including: supplying a monomer stream and a solvent stream to a reactor to perform an oligomerization reaction to prepare a reaction product; supplying a discharge stream from the reactor including the reaction product to a separation device and supplying a lower discharge stream from the separation device to a settling tank; adding an organic flocculant to the settling tank to settle and remove a polymer and supplying the lower discharge stream from the separation device from which the polymer is removed to a high boiling point separation column; and removing a high boiling point material from the lower portion in the high boiling point separation column and supplying an upper discharge stream including an oligomer to a solvent separation column.

Abstract: The present disclosure relates to an apparatus for preparing an oligomer, the apparatus including: a reactor for oligomerizing a feed stream containing a fed monomer; a stirrer inserted into a hole formed in an upper portion of the reactor; and a solvent transfer line extending inward from a side of the reactor, wherein the stirrer includes a rotating shaft vertically extending downward from the upper portion of the reactor, and a blade having a conical shape whose vertex is positioned at a lower end of the rotating shaft and outer diameter increases from a bottom toward a top, and the solvent transfer line has a plurality of spray nozzles formed in a direction toward the blade.

Abstract: Provided is a method of producing an oligomer, the method including: supplying a monomer stream and a solvent stream to a reactor to perform an oligomerization reaction to produce a reaction product; supplying a discharge stream of the reactor to a separation device, and supplying an upper discharge stream of the separation device including an unreacted monomer to the reactor and supplying a lower discharge stream of the separation device to a settling tank; settling a polymer in the settling tank and removing the polymer, and supplying the lower discharge stream of the separation device from which the polymer is removed to a high-boiling point separation column; removing a high-boiling point material from a lower discharge stream of the high-boiling point separation column and supplying an upper discharge stream of the high-boiling point separation column including an oligomer to a solvent separation column; and separating a solvent and the oligomer in the solvent separation column.

Abstract: A hair dye dispenser according to an embodiment of the present invention includes a housing having an opening hole formed on one side of which a hair dye is provided, a plurality of cartridges disposed inside the housing and accommodating at least one dyeing material, a main body in which the plurality of cartridges are rotatably disposed, a main motor for rotating the main body so that a first cartridge of the plurality of cartridges is located adjacent to the opening hole, a discharge module for discharging the dyeing material contained in the first cartridge, and an accommodating body in which a basket accommodating the dyeing material discharged by the discharge module is placed, wherein the discharge module may include an elevating body that pressurizes the first cartridge when moving up and is separated from the first cartridge when moving down.

Abstract: A porous structure according to one embodiment of the present invention is constituted by a frame having a plurality of pores interconnected 3-dimensionally through a plurality of connecting passages. The plurality of pores defined by the frame are distributed in a closest packed state and are interconnected 3-dimensionally through a plurality of connecting passages in a symmetric structure, thus being effective in achieving a maximum porosity of the porous structure. A porous hierarchical structure according to one embodiment of the present invention includes a first porous structure having a plurality of 3-dimensionally interconnected first pores and a second porous structure having a plurality of 3-dimensionally interconnected second pores whose diameter is different from that of the first pores and surrounding and bonded to the first porous structure.