METHOD OF PREPARING ASA GRAFT COPOLYMER, METHOD OF PREPARING THERMOPLASTIC RESIN COMPOSITION INCLUDING ASA GRAFT COPOLYMER, AND METHOD OF MANUFACTURING MOLDED ARTICLE USING THERMOPLASTIC RESIN COMPOSITION

摘要

The present invention relates to a method of preparing an ASA graft copolymer, a method of preparing a thermoplastic resin composition including the ASA graft copolymer, and a method of manufacturing a molded article using the thermoplastic resin composition. More particularly, the present invention provides an ASA graft copolymer having improved thermal stability through addition of an emulsifier in a specific amount range in a seed preparation step and introduction of a multifunctional carboxylic acid having 20 or more carbon atoms or a salt thereof, as an emulsifier, in a shell preparation step and a high-quality thermoplastic resin composition exhibiting excellent impact resistance, such as impact strength and tensile strength, and excellent appearance, such as surface gloss, whiteness, and retention-associated heat discoloration, and causing considerable reduction in the amount of gas generated on a surface of a resin during a high-temperature thermoforming process due to inclusion of the ASA graft copolymer.