ASA resin, also known as AAS resin, is a ternary graft copolymer composed of acrylonitrile (A), styrene (S), and acrylic acid ester (A). Compared to ABS, ASA resin has significantly improved weather resistance due to the introduction of acrylic acid ester rubber without double bonds replacing butadiene rubber. Its weather resistance is about 10 times higher than ABS, while its other mechanical properties, processing performance, electrical insulation, and chemical resistance are similar to ABS. ASA resins are commonly used in the production of outdoor products such as auto parts, outdoor furniture, and building materials such as roof tiles and siding. Used in the production of electrical and electronic components due to its high impact strength as well as its tolerance to UV radiation and chemicals. Used in the production of toys, sports equipment and other consumer products because of its ability to retain its color and physical properties in harsh outdoor environments.