ABS
Summary
ABS is a terpolymer of acrylonitrile (15 to 35 percent), butadiene (5 to 30 percent), and styrene (40 to 60 percent). It is impact-resistant and solvent-cemented into drain-waste-vent pipe, but UV and heat make it yellow and turn it brittle.
Cols
Terminology
- ABS: acrylonitrile butadiene styrene
- DWV: drain, waste, and vent
- Solvent cementing: chemical bonding of parts with solvents
History and demand
Discovery and early use
- Patented in 1948 and commercialized by Borg-Warner in 1954
Composition and production
Raw materials
- Acrylonitrile 15 to 35 percent, butadiene 5 to 30 percent, styrene 40 to 60 percent
Properties
Physical
- Density: 0.9 to 1.53 g/cm3, median 1.07 g/cm3 (about 67 lb/ft3)
- Glass transition: about 105°C (221°F); amorphous, no definite melting point
- Service temperature: about -20 to 80°C (-4 to 176°F)
Mechanical
- Tensile strength: 43 MPa (6.2 ksi)
- Young's modulus: 2.28 GPa (331 ksi)
- Flexural strength: 77 MPa (11.2 ksi)
- Heat deflection temperature: 81°C (178°F) at 1.81 MPa
Thermal and moisture
- Thermal conductivity: 0.1 W/(m·K)
- Thermal expansion: linear coefficient 12 x 10-5 /K, about 6.7 x 10-5 in./in./°F
Fire behavior
- Melts, then boils, and vapors ignite into intense flames; main toxic combustion products are carbon monoxide and hydrogen cyanide
Durability
- UV light or excess heat causes yellowing and brittleness
- Resists aqueous acids and alkalis; poor against alcohols, aldehydes, ketones, and esters
Uses in buildings
Building elements
- Sanitary and Vent Piping: DWV pipe and fittings
Pros and cons
Pros
- Good impact resistance, including at low temperatures
- Solvent-cemented joints
Cons
- Yellows and embrittles under UV
- Attacked by ketones, esters, alcohols, and aldehydes
Manufacturing and cost
Main manufacturers and suppliers
Trade association: Plastics Pipe Institute.
Sources
- Wikipedia: Acrylonitrile butadiene styrene, https://en.wikipedia.org/wiki/Acrylonitrile_butadiene_styrene