The present invention provides a method of preparing an aromatic vinyl-unsaturated nitrile-based copolymer in which, when an aromatic vinyl-unsaturated nitrile-based copolymer in which a content of a structural unit derived from unsaturated nitrile monomers in the copolymer is in the range of 22 to 30 wt % is prepared, oligomer content and unreacted monomer content are decreased, resulting in excellent heat resistance, significantly improved surface quality, and particularly, reduced generation of residue on a product surface when used in a closed high temperature environment and reduced occurrence of mold deposits during injection molding, and an aromatic vinyl-unsaturated nitrile-based copolymer prepared using the method.

A production method for a polymer comprises: a step (A) of polymerizing a raw material monomer to obtain a polymer-containing liquid containing a polymer; a step (B) of separating a collection target component-containing fluid containing a collection target component composed of at least one of a solvent and a residual monomer, from the polymer-containing liquid; a step (C) of supplying the collection target component-containing fluid to a three-product distillation column, and separating a fraction containing an impurity higher in boiling point than the collection target component and a fraction containing an impurity lower in boiling point than the collection target component, to obtain a fraction containing the collection target component of high purity; and a step (D) of performing polymerization using the fraction containing the collection target component of high purity.

A production method for a polymer comprises: a step (A) of polymerizing a raw material monomer to obtain a polymer-containing liquid containing a polymer; a step (B) of separating a collection target component-containing fluid containing a collection target component composed of at least one of a solvent and a residual monomer, from the polymer-containing liquid; a step (C) of supplying the collection target component-containing fluid to a three-product distillation column, and separating a fraction containing an impurity higher in boiling point than the collection target component and a fraction containing an impurity lower in boiling point than the collection target component, to obtain a fraction containing the collection target component of high purity; and a step (D) of performing polymerization using the fraction containing the collection target component of high purity.

A preparation method for an ethylene-vinyl alcohol copolymer capable of obtaining a high-purity ethylene-vinyl alcohol copolymer without an excessive washing process is described herein. According to the present disclosure, an efficiency of the washing process for obtaining the ethylene-vinyl alcohol copolymer after performing saponification on ethylene-vinyl acetate can be increased, thereby improving productivity, and minimizing the amount of wastewater generated.

A preparation method for an ethylene-vinyl alcohol copolymer capable of obtaining a high-purity ethylene-vinyl alcohol copolymer without an excessive washing process is described herein. According to the present disclosure, an efficiency of the washing process for obtaining the ethylene-vinyl alcohol copolymer after performing saponification on ethylene-vinyl acetate can be increased, thereby improving productivity, and minimizing the amount of wastewater generated.

An extruder including a housing, a first material inlet for a mixture at least consisting of a solvent and a dissolved medium, a material outlet, a screw, a screw drive, and at least one distillation region between the inlet and the outlet, which allows an outflow of solvent, and a discharge line for the solvent.

An extruder including a housing, a first material inlet for a mixture at least consisting of a solvent and a dissolved medium, a material outlet, a screw, a screw drive, and at least one distillation region between the inlet and the outlet, which allows an outflow of solvent, and a discharge line for the solvent.

An extruder including a housing, a first material inlet for a mixture at least consisting of a solvent and a dissolved medium, a material outlet, a screw, a screw drive, and at least one distillation region between the inlet and the outlet, which allows an outflow of solvent, and a discharge line for the solvent.

The present invention relates to a method for producing an ethylene-based copolymer, and more particularly, to a method for producing an ethylene-based copolymer capable of increasing process efficiency by preventing plugging and corrosion of a facility. The method for producing an ethylene-based copolymer includes a producing mode and a washing mode of which one is selectively performed. The producing mode includes: a) hyper-compressing primary compressed ethylene, and a mixture including a carboxylic acid-containing comonomer and a polar solvent to produce a compressed material; b) reacting the compressed material to produce a reaction product including an ethylene-based copolymer; and c) separating and recovering unreacted residues from the reaction product and introducing the unreacted residues into the mixture of step a). The washing mode includes: re-supplying the compressed material produced in step a) to step a) as a mixture, without performing step b).

The present invention relates to a method for producing an ethylene-based copolymer, and more particularly, to a method for producing an ethylene-based copolymer capable of increasing process efficiency by preventing plugging and corrosion of a facility. The method for producing an ethylene-based copolymer includes a producing mode and a washing mode of which one is selectively performed. The producing mode includes: a) hyper-compressing primary compressed ethylene, and a mixture including a carboxylic acid-containing comonomer and a polar solvent to produce a compressed material; b) reacting the compressed material to produce a reaction product including an ethylene-based copolymer; and c) separating and recovering unreacted residues from the reaction product and introducing the unreacted residues into the mixture of step a). The washing mode includes: re-supplying the compressed material produced in step a) to step a) as a mixture, without performing step b).