Copolymer for improving heat resistance of aromatic vinyl-vinyl cyanide resin

1. A resin composition, comprising:

5 to 50 mass % of a copolymer for improving heat resistance of aromatic vinyl-vinyl cyanide based resin; and

50 to 95 mass % of an aromatic vinyl-vinyl cyanide based resin; wherein:

the copolymer comprises:

45 to 85 mass % of an aromatic vinyl monomer unit;

5 to 45 mass % of a (meth)acrylic acid ester monomer unit; and

10 to 20 mass % of an unsaturated dicarboxylic acid anhydride monomer unit;

and wherein

the copolymer has a total light transmittance of 88% or more, the total light transmittance being measured in accordance with ASTM D1003 for a sample with 2 mm-thickness.

2. The resin composition of claim 1 , comprising:

50 to 80 mass % of the aromatic vinyl monomer unit;

8 to 38 mass % of the (meth)acrylic acid ester monomer unit; and

12 to 18 mass % of the unsaturated dicarboxylic acid anhydride monomer unit.

3. The resin composition of claim 1 , wherein the weight average molecular weight (Mw) of the copolymer is 10×10 4 to 20×10 4 .

4. The resin composition of claim 1 , wherein the aromatic vinyl-vinyl cyanide based resin comprises:

77 to 90 mass % of an aromatic vinyl monomer unit; and

10 to 23 mass % of a vinyl cyanide monomer unit.

5. A molded body comprising a resin composition of claim 1 .