Abstract: The present invention relates to a method of preparing an ABS graft copolymer and a method of preparing a thermoplastic resin composition including the ABS graft copolymer. More specifically, the present invention relates to a method of preparing an ABS graft copolymer, in which a predetermined amount of a vinyl aromatic compound and a predetermined amount of a vinyl cyanide compound are grafted to a small-diameter rubber latex before enlarging particle size of the small-diameter rubber latex is performed, and then enlarging particle size of the small-diameter rubber latex is performed by adding a certain amount of a polymer coagulant, and to a method of preparing a thermoplastic resin composition including the ABS graft copolymer. According to the present invention, latex stability may be improved, and an ABS graft copolymer having excellent impact resistance may be prepared.

Abstract: Disclosed is a method of preparing a graft copolymer and a method of preparing a thermoplastic resin composition including the prepared graft copolymer. Also disclosed is a method of preparing a graft copolymer including a process of adding an aromatic vinyl monomer and a vinyl cyanide monomer to a conjugated diene rubber latex that is enlarged with a polymer particle diameter control agent that has a specific glass transition temperature and an average particle diameter in a specific ratio to an average particle diameter of a conjugated diene rubber latex, and graft-polymerizing the same; and a method of preparing a thermoplastic resin composition including the prepared graft copolymer. Also disclosed is a graft copolymer prepared using the conjugated diene rubber latex enlarged with the polymer particle diameter control agent exhibiting the synergistic effect of improving both impact strength and fluidity.

Abstract: The present invention relates to a method of preparing an ABS graft copolymer and a method of preparing a thermoplastic resin composition including the ABS graft copolymer. More specifically, the present invention relates to a method of preparing an ABS graft copolymer, in which a predetermined amount of a vinyl aromatic compound and a predetermined amount of a vinyl cyanide compound are grafted to a small-diameter rubber latex before enlarging particle size of the small-diameter rubber latex is performed, and then enlarging particle size of the small-diameter rubber latex is performed by adding a certain amount of a polymer coagulant, and to a method of preparing a thermoplastic resin composition including the ABS graft copolymer. According to the present invention, latex stability may be improved, and an ABS graft copolymer having excellent impact resistance may be prepared.