ABS is a resin used in plastics processing, mainly for injection molding and extrusion. This page covers its grade classification and a real limitation worth knowing before specifying it for outdoor use.
What is it?
ABS is a three-monomer resin — acrylonitrile, butadiene, and styrene — classified under ASTM D4673 for molding and extrusion, including alloys, and covering grouped classes and grades such as reinforced and lubricated variants.
Why should I use it?
- A single classification system covers its many grades — see “What is it?” above.
- A specific, measurable weakness under prolonged UV exposure — see Limitations.
How it’s used
In Plastics & Polymers, ABS is used for injection-molded and extruded parts.
Limitations — when it isn’t the right choice
- Unprotected, prolonged outdoor UV exposure is a real, measured weakness. A 2023 peer-reviewed study (using LEGO® bricks as ABS test samples) found a two-step photo-degradation process: the polybutadiene component photo-oxidizes first, and after more than 120 hours of exposure the styrene-acrylonitrile portion begins to depolymerize. After 1,390 hours of UV exposure, the material’s glass transition temperature dropped by 19°C — a measurable loss of thermal/structural stability. This was documented in one specific product’s material; it’s a real degradation mechanism to weigh for outdoor use, not necessarily identical across every industrial ABS grade.