Thermoplastic resin composition, method of preparing the same, and molded article manufactured using the same

A method of preparing a thermoplastic resin composition, comprising kneading and extruding, at 180 to 300° C. and 80 to 400 rpm:

• an alkyl (meth)acrylate-aromatic vinyl compound-vinyl cyanide compound graft copolymer (A) comprising:
• a polymer seed comprising:
• 70 to 85% by weight of a first alkyl (meth)acrylate and
• 15 to 30% by weight of a first aromatic vinyl compound,
• a rubber core surrounding the polymer seed and comprising:
• 78 to 90% by weight of a first alkyl acrylate and
• 10 to 22% by weight of a second aromatic vinyl compound, and
• a graft shell surrounding the rubber core and comprising:
• 65 to 80% by weight of a third aromatic vinyl compound,
• 14 to 25% by weight of a first vinyl cyanide compound, and
• 3 to 15% by weight of a second alkyl acrylate;
• and
• a non-graft copolymer (B) comprising:
• a second alkyl (meth)acrylate,
• a fourth aromatic vinyl compound, and
• a second vinyl cyanide compound,
• wherein the graft copolymer (A) satisfies both Equations 1 and 2 below:
• 200
• ≤
• 2
• ⨯
• r
• ⁢
• 2
• ≤
• 300
• Equation
• ⁢
• 1
• 25
• ≤
• r
• ⁢
• 2
• -
• r
• ⁢
• 1
• ≤
• 45
• ,
• Equation
• ⁢
• 2
• wherein:
• r1 represents an average radius (nm) from a center of the graft copolymer to a surface of the polymer seed facing the rubber core, and
• r2 represents an average radius (nm) from the center of the graft copolymer to a surface of the rubber core facing the graft shell.