Abstract: A method of preparing a graft copolymer includes a step of performing coagulation by adding an acid coagulant to 100 parts by weight (based on solids) of graft copolymer latex prepared by graft-polymerizing an aromatic vinyl compound and a vinyl cyanide compound onto conjugated diene rubber latex; and a step of performing coagulation once more by adding a salt coagulant thereto. In a resulting graft copolymer, coagulation efficiency may be improved and the gloss of the prepared graft copolymer may be increased. In addition, since a b-value measured using a Hunter lab colorimeter and a b-value measured after being left at 250° C. for 15 minutes are low, the graft copolymer may have excellent color characteristics. In addition, since heating loss is low and scorch time is long, the graft copolymer may have excellent processing characteristics.

Abstract: Provided is a method of preparing a diene-based rubber polymer, which includes: adding each of a diene-based monomer, a molecular-weight regulator, an initiator, and an emulsifier to a reactor a first time and carrying out polymerization; adding a molecular-weight regulator to the reactor a second time when a polymerization conversion rate of 48 to 72% is reached and carrying out polymerization; adding a diene-based monomer to the reactor a second time when a polymerization conversion rate of 63 to 77% is reached and carrying out polymerization; adding each of an initiator and an emulsifier to the reactor a second time when a polymerization conversion rate of 68 to 81% is reached and carrying out polymerization; and adding each of an initiator and an emulsifier to the reactor a third time when a polymerization conversion rate of 85 to 91% is reached and carrying out polymerization.

Abstract: Provided are a method of preparing a graft copolymer, a graft copolymer, and a thermoplastic resin molded article. The method of preparing a graft copolymer includes 1) adding a conjugated diene-based monomer and performing polymerization to prepare a conjugated diene-based polymer; and 2) adding the conjugated diene-based polymer, an aromatic vinyl monomer, and a vinyl cyan monomer and performing polymerization to prepare a graft copolymer, wherein an emulsifier having an APHA color value of 50 or less and a critical micelle concentration of 1 to 50 g/l is added, so that excellent polymerization stability, colorability, light resistance, and surface clarity are exhibited.

Abstract: A copolymer is prepared by graft-polymerizing 20 to 40% of an aromatic vinyl compound and 1 to 20% of a vinyl cyanide compound onto 50 to 70% of conjugated diene rubber latex having a solids content of 30 to 65% by weight, coagulating the latex by adding 0.04 to 0.27 parts by weight of a first nonionic polymer coagulant, and 0.47 to 1.65 parts by weight of a second cationic polymer coagulant or 0.73 to 3.35 parts by weight of a second anionic polymer coagulant to 100 parts by weight (based on solids) of the prepared graft copolymer latex. When the second coagulant is the cationic polymer coagulant, the total weight of coagulant is 0.7 to 1.7 parts by weight, and when the second coagulant is the anionic polymer coagulant, the total weight of coagulant is 0.97 to 3.37 parts by weight.

Abstract: A method of preparing a graft copolymer includes a step of performing coagulation by adding an acid coagulant to 100 parts by weight (based on solids) of graft copolymer latex prepared by graft-polymerizing an aromatic vinyl compound and a vinyl cyanide compound onto conjugated diene rubber latex; and a step of performing coagulation once more by adding a salt coagulant thereto. In a resulting graft copolymer, coagulation efficiency may be improved and the gloss of the prepared graft copolymer may be increased. In addition, since a b-value measured using a Hunter lab colorimeter and a b-value measured after being left at 250° C. for 15 minutes are low, the graft copolymer may have excellent color characteristics. In addition, since heating loss is low and scorch time is long, the graft copolymer may have excellent processing characteristics.

Abstract: The present invention relates to a method for preparing a conjugated diene-based polymer, which includes a step of preparing a conjugated diene-based polymer by initiating and carrying out polymerization while continuously adding conjugated diene-based monomers to a reactor, and in which an emulsifier is dividedly added before the initiation of the polymerization and when a polymerization conversion rate of 31% to 80% is reached. More particularly, the present invention relates to: a method for preparing a conjugated diene-based polymer and a method for preparing a graft copolymer including the method for preparing a conjugated diene-based polymer, by which a total usage amount of an emulsifier can be reduced.

Abstract: A method of preparing a diene-based rubber latex, a method of preparing an ABS-based graft copolymer including the same, and a method of manufacturing an ABS-based injection-molded article include preparing an in-situ bimodal rubber latex, in which a small-diameter polymer and a large-diameter polymer are formed in a desired ratio, by controlling contents, addition time points, and types of reactants when a conjugated diene based monomer, a crosslinking agent with a long linear chain end, an emulsifier including a multimeric acid of an unsaturated fatty acid or a metal salt thereof, and a molecular weight regulator are polymerized.

Abstract: The present invention relates to a method of preparing an ABS-based resin composition and a method of manufacturing an ABS-based injection-molded article including the same. More particularly, the present invention provides a method of preparing an ABS-based resin composition using a multimeric acid of unsaturated fatty acid or a metal salt thereof, as an emulsifier, in a diene-based rubber latex polymerization step and an ABS-based graft polymerization step. In accordance with the present invention, when an ABS-based resin composition is prepared using a multimeric acid of unsaturated fatty acid or a metal salt thereof as an emulsifier, stability of polymerization is secured and surface characteristics, such as surface gloss or sharpness, of an ABS-based injection-molded article are improved.

Abstract: The present invention relates to a method of preparing an ABS-based graft copolymer having improved impact strength and an ABS-based injection-molded article including the same. More particularly, the present invention provides an ABS-based copolymer resin having improved impact strength by optimizing structures of large-diameter diene-based rubber latex particles and a matrix structure between ABS-based copolymer particles and a SAN resin through introduction of a multimeric acid of an unsaturated fatty acid or a metal salt thereof as an emulsifier in a large-diameter diene-based rubber latex polymerization step and an ABS graft polymerization step.

Abstract: The present invention relates to a thermoplastic polymer, a method of preparing the thermoplastic polymer, and a thermoplastic polymer composition including the thermoplastic polymer. More particularly, the present invention provides a thermoplastic polymer reducing the amount of gas generated in high-temperature extrusion and injection-molding processes to improve surface gloss and definition of a resin and provides superior latex stability when a chain-type fatty acid or a salt thereof having a specific branch group or functional group is included as an emulsifier during shell polymerization of a thermoplastic polymer including a core-shell structure, a method of preparing the thermoplastic polymer, and a thermoplastic polymer composition including the thermoplastic polymer.

Abstract: The present invention relates to a method for preparing large-sized diene-based rubber latex, and an acrylonitrile-butadiene-styrene graft copolymer comprising the same. More particularly, it relates to a method for preparing large-sized diene-based rubber latex having improved impact strength by controlling content and time of addition of a cross-linking agent and an emulsifier having critical micelle concentration (CMC) of 150 mg/L or less during preparation of the large-sized rubber latex, large-sized diene-based rubber latex prepared therefrom, and an acrylonitrile-butadiene-styrene graft copolymer and thermoplastic resin comprising the same.

Abstract: The present disclosure relates a method of preparing a rubbery polymer, a rubbery polymer, and a graft copolymer and thermoplastic resin composition including the rubbery polymer. In accordance with the present disclosure, a rubbery polymer, in which a large-diameter rubbery polymer and a small-diameter rubbery polymer are formed in a desired ratio by controlling the contents, addition time points, and types of a crosslinking agent, an emulsifier, and a molecular weight regulator when a conjugated diene monomer, the crosslinking agent, the molecular weight regulator, and the emulsifier are polymerized, and a graft copolymer and thermoplastic resin composition having excellent surface gloss and mechanical properties are provided.

Abstract: The present invention relates to a method for preparing a diene-based rubber polymer having relatively low gel content and high swelling index while having high polymerization conversion rate, a diene-based rubber polymer prepared therefrom and an acrylonitrile-butadiene-styrene graft copolymer with a core-shell structure comprising the same as a core. Accordingly, the method for preparing a diene-based rubber polymer and the acrylonitrile-butadiene-styrene graft copolymer with a core-shell structure comprising the diene-based rubber polymer prepared therefrom can be easily applied to the industries requiring them, in particular, an impact reinforcing agent industry.

Abstract: Provided are a method of preparing a graft copolymer, a graft copolymer, and a thermoplastic resin molded article. The method of preparing a graft copolymer includes 1) adding a conjugated diene-based monomer and performing polymerization to prepare a conjugated diene-based polymer; and 2) adding the conjugated diene-based polymer, an aromatic vinyl monomer, and a vinyl cyan monomer and performing polymerization to prepare a graft copolymer, wherein an emulsifier having an APHA color value of 50 or less and a critical micelle concentration of 1 to 50 g/l is added, so that excellent polymerization stability, colorability, light resistance, and surface clarity are exhibited.

Abstract: The present invention relates to a method for preparing an acrylonitrile-butadiene-styrene graft copolymer having improved impact strength, which comprises: a step of preparing diene-based rubber latex by adding an acrylate-based cross-linking agent (Step 1); and a step of inserting the same cross-linking agent with the acrylate-based cross-linking agent, an aromatic vinyl-based compound and a vinyl cyan-based compound to the diene-based rubber latex and then subjecting thereof to graft copolymerization (Step 2), an acrylonitrile-butadiene-styrene graft copolymer prepared by the method, and an acrylonitrile-butadiene-styrene thermoplastic resin comprising the same.

Abstract: The present invention relates to a method for preparing an acrylonitrile-butadiene-styrene graft copolymer having improved impact strength, which comprises: a step of preparing diene-based rubber latex by adding an acrylate-based cross-linking agent (Step 1); and a step of inserting the same cross-linking agent with the acrylate-based cross-linking agent, an aromatic vinyl-based compound and a vinyl cyan-based compound to the diene-based rubber latex and then subjecting thereof to graft copolymerization (Step 2), an acrylonitrile-butadiene-styrene graft copolymer prepared by the method, and an acrylonitrile-butadiene-styrene thermoplastic resin comprising the same.

Abstract: The present invention relates to a method for preparing a diene-based rubber latex having improved impact strength, gloss and flexibility, diene-based rubber latex prepared therefrom, and an acrylonitrile-butadiene-styrene graft copolymer having improved impact strength and production yield while having reduced rubber solid content ratio by comprising the same.

Abstract: The present invention relates to a method of preparing an ABS-based graft copolymer having improved impact strength and an ABS-based injection-molded article including the same. More particularly, the present invention provides an ABS-based copolymer resin having improved impact strength by optimizing structures of large-diameter diene-based rubber latex particles and a matrix structure between ABS-based copolymer particles and a SAN resin through introduction of a multimeric acid of an unsaturated fatty acid or a metal salt thereof as an emulsifier in a large-diameter diene-based rubber latex polymerization step and an ABS graft polymerization step.

Abstract: The present invention relates to a method of preparing an ABS-based resin composition and a method of manufacturing an ABS-based injection-molded article including the same. More particularly, the present invention provides a method of preparing an ABS-based resin composition using a multimeric acid of unsaturated fatty acid or a metal salt thereof, as an emulsifier, in a diene-based rubber latex polymerization step and an ABS-based graft polymerization step. In accordance with the present invention, when an ABS-based resin composition is prepared using a multimeric acid of unsaturated fatty acid or a metal salt thereof as an emulsifier, stability of polymerization is secured and surface characteristics, such as surface gloss or sharpness, of an ABS-based injection-molded article are improved.

Abstract: A method of preparing a diene-based rubber latex, a method of preparing an ABS-based graft copolymer including the same, and a method of manufacturing an ABS-based injection-molded article include preparing an in-situ bimodal rubber latex, in which a small-diameter polymer and a large-diameter polymer are formed in a desired ratio, by controlling contents, addition time points, and types of reactants when a conjugated diene based monomer, a crosslinking agent with a long linear chain end, an emulsifier including a multimeric acid of an unsaturated fatty acid or a metal salt thereof, and a molecular weight regulator are polymerized.