PLA and ABS are common materials in manufacturing, we get asked that PLA vs ABS, what’s the difference? From the definition to properties to application, we’ll explain the PLA and ABS in detail, also compare ABS and PLA filaments in printing.
PLA, the abbreviation of Polylactic Acid, is a thermoplastic polyester and biodegradable plastic, made from renewable resources like starch. It is formed through condensation polymerisation (loss of a water molecule). PLA was first developed in 1954 and commercially produced in the 1990s, then growing in numbers.
Properties of PLA
Polymer density: 1.21-1.25 g/cm3
Tensile strength: 21-60 MPa
Tensile modulus: 0.35-3.5 GPa
Ultimate strain: 2.5-6%
Specific tensile strength: 16.8-48.0 Nm/g
Specific tensile modulus: 0.28-2.80 kNm/g
Glass transition temperature: 45-60 ℃
Melting temperature: 150-162 ℃
Common Applications and Uses of PLA – What is PLA Used for?
PLA is the most extensively researched and utilized renewable aliphatic polyester, it has a proven potential either to replace conventional petrochemical-based polymers for industrial applications or as a leading biomaterial for numerous medical applications. PLA is a really good choice for 3D printing, PLA is easy to print with relatively low temperatures, it will stick well enough to most bed surfaces except maybe raw aluminum or bare PCBs, and it’s actually mechanically quite strong. Common uses of PLA also including plastic bags, plastic containers, garbage bags, food wraps, textiles fibers, automotive parts and more.
ABS (Acrylonitrile butadiene styrene) is a common thermoplastic polymer and a terpolymer made by polymerizing styrene and acrylonitrile in the presence of polybutadiene. Three monomers, mixed together and linked together, forming the copolymer ABS. The butadiene in this mix gives ABS its typical milky, off-white color, and depending on how the ABS plastic is manufactured, it remains as larger or smaller particles within the mix, it also gives ABS its toughness, which it is known for. ABS plastic is rigid, tough, impact-resistant with moderate use temperature, which helps it a daily use plastic. It is easy to mold, with low shrinkage, less warpage, and provides a good surface finish.
Properties of ABS
Density: 1.02-1.21 g/cm3
Glass transition temperature: 90-102 ℃
Young Modulus: 1.79-3.2 GPa
Toughness: 200-215 J/m
Strength at Yield (Tensile): 29.6-48 MPa
Strength at Break (Tensile): 29.8-43 MPa
Stiffness (Flexural Modulus):1.6-2.4 GPa
Hardness Shore D: 100
Elongation at Yield: 1.7-6%
Elongation at Break: 10-50%
Applications of Uses of ABS – What is ABS Used for?
The properties and characteristics make the ABS injection molded parts and extruded products are widely used in pipe systems. Other applications of ABS plastic including musical instruments, keyboard keycaps, golf club heads, automotive rim components, medical & surgical non-absorbable sutures, tendon prostheses, drug-delivery systems tracheal tubes, enclosures for electrical and electronic assemblies, toys, household and consumer goods, colorant, etc. ABS is also used as a filament for 3D printing by FDM (fused deposition modeling), and ideal for the production of prototypes.
PLA and ABS are similar in some aspects, such as the price, you can find more budget choices based on your purposes. However, they differ a lot when it comes to strength, heat resistance, other properties and applications.
– Compared with PLA, ABS takes advantage of ductility, flexural strength and elongation before breaking, which makes it a preferred choice for many prototyping applications. If the shape matters more than function, PLA printed part seems more popular.
– The glass transition temperature of ABS is higher than that of PLA, so ABS has higher heat resistance than PLA, which easily loses its structural integrity in a high-temperature environment. However, ABS tends to crack in a cold environment, while PLA doesn’t. PLA performs best in projects with low mechanical or thermal requirements because of its low solvent and water resistance.
2. Surface finish: FDM 3D printing makes both ABS and PLA prints get visible layers. ABS usually comes in a matte finish, and PLA has a glossier finish.
3. Biodegradability: PLA is a bioabsorbable polymer and one of the most promising biopolymers due to the fact that the monomers may be produced from non-toxic renewable feedstock as well as due to being a naturally occurring organic acid. ABS is not biodegradable, but it is recyclable.
– PLA is easier to print with than ABS, and it is suitable for 3D printing parts where aesthetics values and fine details required. PLA is also commonly used by beginners and hobbyists who just getting started in the world of 3D printing.
– ABS is a better choice when strength, ductility, thermal stability and machinability are important. Its durability makes it common for end-use products such as protective cases.
– Overall, PLA is more popular in 3D printing, even though it’s not suitable for heavy-duty functional parts, while ABS is a more industrial and engineering material that can be used in CNC machining and injection molding.
ABS vs PLA filament, what’s the difference?
1. ABS printing needs higher nozzle and bed temperatures than PLA, especially the print bed. Generally, ABS filaments need a bed temperature between 80 ℃ to 110 ℃, PLA filaments usually apply 60 ℃ bed and even no heated bed.
2. When it comes to odors, the toxicity of ABS is obviously higher than that of PLA, and it can produce a terrible odor. When the shell is lifted, smoke may be released suddenly, making the smell sometimes intolerable.
3. ABS is a bit stronger than PLA, which resulting in its printing difficulty to some extent.
4. ABS prints tend to be less brittle than PLA parts, which means that the flexibility of ABS is better.