ABS (short for Acrylonitrile Butadiene Styrene) is a highly rigid thermoplastic and amorphous polymer. It’s an incredibly versatile type of plastic used for many different kinds of manufacturing.
ABS is popular due to its low production cost, machining ability, and unique characteristics. This type of engineering plastic is extremely useful, especially in 3D printing, because it becomes flexible (or moldable) above a particular temperature and hardens when cooled.
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Chemical Formula: (C8H8·C4H6·C3H3N)n
Average Density: 1.07 gram/cm3
Tensile Strength: 43 MPa
Heat Resistance: 110ºC
Melting Point: 200°C
What Is ABS Made Of?
ABS contains three monomers:
1. Acrylonitrile: is synthetically produced from ammonia and propylene. It’s a colorless, volatile liquid with a pungent, garlic-like odor. This monomer makes ABS chemically resistant and stable at high temperatures.
2. Butadiene: is a synthetic, colorless gas with a mild aromatic odor. Although there are no consumer uses of butadiene, it is used as a monomer and chemical intermediate to produce various polymers. In ABC, this component contributes to toughness and impact strength.
3. Styrene: is a synthetic, colorless liquid that evaporates easily and has a sweet smell. Billions of pounds are produced every year to make products like plastic, pipes, fiberglass, and rubber. It provides processability and rigidity to ABC polymer.
Yellow ABS Granules
ABS is made by polymerizing acrylonitrile and styrene in the presence of polybutadiene. The proportion can vary from 40% to 60% styrene, 15% to 35% acrylonitrile, and 5% to 30% butadiene. This produces a large chain of polybutadiene intersecting with smaller chains of poly(styrene-co-acrylonitrile).
Physical and Chemical Properties of ABS
The versatility of properties of the ABS polymer contributes largely to its popularity across different industries.
For example, ABS has incredible tensile strength and is resistant to chemical corrosion and physical impact, which enable the finished product to withstand heavy use and adverse external conditions. It also has a low melting point, which allows its easy use in the 3D printing and injection molding process.
The polymer can be easily molded, sanded, and shaped. The finished product has a glossy surface finish that can be glued and painted. ABS materials absorb colors, enabling the final products to be dyed in precise shades to meet project specifications.
ABS’s ability to withstand being heated and cooled several times make it suitable for recycling. And since it has low electricity and heat conductivity, it can be used to make products that require electrical insulation protections. The material also provides high impact resistance and can absorb shock effectively.
Dielectric Constant: 2.7-3.2
Dielectric Strength: 15.7-34 kV/mm
ABS plastics are resistant to concentrated phosphoric and hydrochloric acids, aqueous acids, alkalis, and vegetable and mineral oils.
However, they are attacked by concentrated nitric and sulfuric acids and are swollen by aromatic hydrocarbons and glacial acetic acid. They offer poor resistance to chlorinated solvents and aldehydes and get easily dissolved in ketones and esters.
Gamma Radiation Resistance: Good
UV Light Resistance: Poor
ABS can be easily blended with other materials to manufacture various high-quality yet cost-effective commercial products.
ABS is a non-toxic thermoplastic. It is stable and doesn’t contain any carcinogens. No serious health effects as a result of ABS exposure have yet been reported. Therefore, it is considered a safe plastic for making legos and toys.
But because of a few limitations, ABS materials are not suitable for making medical implants.
Like any other material, ABS has its own shortcomings. Its low melting point makes it unsuitable for medical implants and high-temperature applications. It also doesn’t stand up well to ultraviolet exposure unless it is thoroughly protected.
When burned, ABS plastics generate high amounts of smoke, causing air pollution concerns. Carbon monoxide and hydrogen cyanide are the two most toxic products of ABS combustion or pyrolysis.
The inability of ABS to withstand sunlight caused one of the most expensive automobile recalls in the United States history in 1995. This failure was caused by the degradation and fracture of the seat belts’ polymeric release buttons, which affected more than 8.4 million vehicles.
Fortunately, these limited negatives points haven’t prevented ABS from providing efficient, high-quality products for thousands of different applications. This top-performing thermoplastic still has a wide variety of benefits and uses.
Machine Grade ABS
ABS is manufactured in many different grades. However, for accurate machining of structural components, Machine Grade ABS is preferred.
It can be easily machined through conventional machining methods, such as milling, drilling, and sawing. This material grade is mostly available in rods and sheets as per the customers’ requirements.
ABS rods in different colors
Generally, ABS rods are 8 feet long and 6-inch wide. ABS sheets are available in two forms: Compression-molded (up to 4 inches thick) and Extruded sheets (with better thickness tolerance than molded sheets).
ABS finds use in several industrial and commercial applications. Its unique characteristics make it a good base material for a wide range of industries, including electrical applications, automobiles, toys, and sports equipment.
Today, more than 6,000 ABS grades are available in the market, which are used in various household products, appliances, electronics, automotive, pipes, hoses and fittings, and more.
More specifically, ABS can be used to produce lightweight molded products like musical instruments, golf club heads (for absorbing shocks), protective headgear, support blocks, pipes (including waste, drain, or pipe joints), automotive body components, wheel covers, LEGO bricks, toys, and kitchen appliances.
When added with certain stabilizers, ABS can be a highly cost-effective and durable choice for outdoor enclosures. ABS materials having a diameter of less than 1 μm can be used as the colorant in some tattoo inks.
ABS is also one of the most common 3D printing materials. It is used in Fused Deposition modeling — a popular 3D printing process that uses a continuous filament of ABS.
ABS 3D prints are highly stable and suitable for many different post-processing options, such as sanding, gluing, filling, and painting. The two popular forms of ABS filaments are ABS-FR (fire resistant) and ABS-ESD (electrostatic discharge). They are used for printing electrostatically sensitive parts and refractory prefabricated components.
In 2020, the ABS global market was valued at $25.95 billion. According to the Global Market Insights report, this figure is expected to increase at a CAGR of 6.3% from 2021 to 2027.
The business growth is fueled by the rising demand for household appliances, such as microwave ovens, washing machines, and dryers, coupled with increasing consumer spending on appliances.
The use of ABS plastics is in the automobile industry is significantly increasing. Regulatory demands to decrease vehicles’ weight to bring down emissions is another positive factor that would accelerate the growth of the ABS industry.
Overall, the appliances and automobile markets are expected to drive the demand for ABS in North America and Europe, while in China, India, and Indonesia, the electronics segment would be the key driver, followed by the automobile sector.
ABS is also extensively used in plastic sheets, pipes, and fittings. Advances in materials science and product innovations such as ABS alloys with improved strength will propel product development. Furthermore, chemical resistance, superior mechanical characteristics, and design flexibility will encourage the ABS scope in various end-use industries.