acrylonitrylbutadienstyren

Acrylonitrile-butadiene-styrene, commonly abbreviated ABS, is a widely used amorphous thermoplastic polymer. It is a terpolymer of styrene, acrylonitrile and polybutadiene. The combination provides a balance of rigidity, chemical resistance and toughness, making ABS suitable for mass production by injection molding and extrusion.

ABS is typically formulated as a three-phase system: a styrene–acrylonitrile (SAN) rigid matrix with a dispersed polybutadiene rubber phase. Typical weight fractions are around 60–70% styrene, 15–35% acrylonitrile and 5–25% butadiene. Rubber content increases impact resistance, especially at low temperatures. Variants with different ratios exist, including high-impact ABS (HIPS) with more rubber.

Processing and properties: ABS processes well by injection molding, extrusion and, in some cases, 3D printing. It offers good impact resistance, toughness and surface finish, along with moderate heat resistance and easy colorability. Its glass transition is around 100°C, and it is more chemically resistant than polystyrene but can be attacked by some solvents. ABS typically shows good dimensional stability and electrical insulation.

Applications: ABS is used for consumer electronics housings, automotive interior parts, toys (including LEGO bricks), housings for power tools and many household products because of its combination of toughness and aesthetic appeal. It is valued for its machinability and ability to produce smooth, glossy surfaces.

Safety and disposal: ABS is not biodegradable but is recyclable through mechanical recycling where facilities exist. Combustion can release toxic gases such as styrene and acrylonitrile; proper ventilation is required. Chemical recycling is an area of ongoing development.