What is PLA Filament? Composition, Benefits, and Uses

PLA filament is one of the most commonly used materials in 3D printings, both for beginners and experienced users. However, what is PLA filament, and why has it become the industry standard in additive manufacturing? This guide explores the fundamentals of Polylactic Acid, its advantages, and its diverse applications.

What is PLA Filament?

Polylactic Acid (PLA) is mechanically biodegradable thermoplastic polymer synthesized from renewable raw materials such as corn starch, or sugar cane. In contrast to the petroleum-derived plastics, PLA is a so-called eco-friendly option which provides, besides its sustainability, also the possibility of 3D printing without inconvenience.

Due to its low melting point, excellent layer adhesion, and minimal warping, PLA filament is ideal for a wide range of applications, from rapid prototyping to artistic creations. Moreover, its biodegradability and low carbon footprint also make it a suitable option for sustainable users.

In the sections below, we will take a closer look at what PLA filament is, its composition, properties, and the many ways it is utilized in the world of 3D printing.

PLA Filament: Composition and Properties

PLA filament is a bio-based thermoplastic that softens when heated and fixes when cold, which is ideal for additive manufacturing. It is generally sold on a spooled basis with common diameters of 1.75mm or 2.85mm to make it compatible with a wide range of 3D printers. There are large-scale manufacturing process that also incorporate PLA filament in pellet format for injection molding or high-format three-dimensional (3D) printing.

Printed with PLA filament is a salient characteristic of its environmental friendliness. It is biodegradable under industrial composting conditions, providing a sustainable replacement of conventional plastics. Furthermore, PLA releases very few fumes and is nontoxic, which means it is safer for indoor printing environments.

Why is PLA Filament So Popular?

PLA’s ubiquitous deployment can be explained through the convenience that it offers in the form of:

• Ease of Printing  Requires lower temperatures, adheres well to print beds, and has minimal warping.
• High Print Quality  Produces smooth, detailed prints with excellent dimensional accuracy.
• Eco-Friendliness  Consists of renewable source development and biodegradability under specific conditions.
• Low Emissions  Releases fewer odors and harmful particles compared to other filaments like ABS.

Common Applications of PLA Filament

PLA is widely used across various industries, including:

• Prototyping  Engineers and designers use PLA for quick, cost-effective concept models.
• Education  Schools and universities prefer PLA for its ease of use and safety.
• Art and Design  Ideal for intricate sculptures, jewelry, and decorative pieces.
• Medical Models  Used in anatomical models and educational tools.

Top PLA Filament Brands

There are many reputable suppliers of PLA filament, each offering unique formulations:

1. Hatchbox – Affordable and reliable, perfect for beginners.
2. Polymaker–Provides strong alternatives such as PolyMax PLA and versatile PolyLite PLA.
3. Prusament (by Prusa Research)  Known for high precision and quality control.
4. eSun – Offers various PLA options, including enhanced PLA+.
5. ColorFabb  Specializes in unique PLA blends, such as PLA/PHA for added durability.
6. MatterHackers  Provides PRO Series PLA in a variety of vibrant colors.

Understanding PLA: Composition and Key Properties

Polylactic acid (PLA) is a bioabsorbable thermoplastic polymer consisting of lactic acid monomers esterified with one another. As a linear aliphatic polyester, it is widely used in 3D printing due to its ease of use, sustainability, and favorable mechanical properties.

How is PLA Made?

PLA is obtained from renewable plant-based materials that are mainly carbohydrates, like corn starch, cassava and sugarcane. The manufacturing process begins with starch extraction, which is then broken down into glucose through enzymatic hydrolysis. Polylactic acid (PLA) is produced by microorganism fermentation of this glucose to lactic acid followed by condensation polymerization.

Key Physical Properties of PLA

PLA filament is well known for its suitability in terms of strength, simplicity and biodegradability. Below are some of its essential characteristics:

• Tensile Strength: 50-70 MPa, ensuring strong and durable prints.
• Density: Approximately 1.24 g/cm³, providing a lightweight structure.
• Melting Point: 150-160°C, making it easy to extrude at lower temperatures.
• Glass Transition Temperature: 60-65°C, affecting heat resistance.
• Elongation at Break: 2.5-6%, offering moderate flexibility.
• Biodegradability: Fully compostable under industrial conditions within 3-6 months.

PLA filament vs. Other Common 3D Printing Plastics

PLA’s properties make it distinct from other widely used filaments like ABS, PETG, and Nylon. Below is a comparison of key attributes:

Property	PLA	ABS	PETG	Nylon
Tensile Strength (MPa)	50-70	40-60	50-70	70-85
Density (g/cm³)	1.24	1.04	1.27	1.13
Melting Point (°C)	150-160	210-240	230-250	220-260
Biodegradability	Yes	No	No	No
Print Bed Temperature (°C)	20-60	80-110	70-90	70-100

Why PLA is Ideal for 3D Printing

PLA low melting point enables low energy consumption extrusion. Due to good shrinkage and warping shrinkage, it has the advantage of better dimensional accuracy and good adhesion to the print bed. Semi-crystalline it is, PLA filament keeps good structural stability without shrinkage, so it’s well suited for both beginners and experts. Furthermore, PLA filament does not release significant fumes and it has almost undetectable odor, so it can be used in house or office use environments.

Enhanced PLA Variants: Tough PLA (PLA+) and PLA Blends

PLA+ (also referred to as Tough PLA) is an upgraded version of basic PLA that is designed to increase impact capacity, deformability, and tensile modulus. Although PLA is fairly brittle, PLA+ contains an additive that makes it more robust and thus applicable to more challenging uses, without losing its easy-to-fabricate character.

Furthermore, PLA may be compounded with other thermoplastics in order to obtain hybrid fibers with tailored characteristics:

• PLA + ABS: Improves heat resistance and durability.
• PLA + PETG: Enhances toughness and chemical resistance.
• PLA + TPU: Materials  Increases flexibility, thus becoming suitable for applications, e.g., on the surface of a smart phone case and other wearables.

Optimizing 3D Printing with PLA filament

Polylactic Acid (PLA) is one of the easiest-to-use materials for 3D printing, however, the optimal results obtained cannot be achieved without fine-tuning of specific print parameters. The extruder temperature, in general, ranges from 180°C to 220°C, and 200°C is an adequate initial temperature. PLA also has a low bed temperature requirement—usually 20°C to 60°C—and in some cases, a heated bed isn’t necessary. On the other hand, a moderate warmth of the bed (40°C) can be beneficial for an optimal first-layer adhesion.

Optimal cooling is very important for satisfactory PLA prints, especially for complex geometries and overhang. Especially printers, a cooling fan is usually provided, which will be set to 100% after the first layer to quickly harden each layer together to ensure a sharp detail.

Best Practices for High-Quality PLA Prints

For the purpose of improving print quality and minimizing errors, the following is recommended:

• Use a reliable print surface  PLA sticks well to glass, PEI sheets, or specialty build plates.
• Optimize layer height  A 0.2mm layer height is a good baseline, but adjusting this can impact print speed and detail.
• Adjust print speed – Speed of 40-60 mm/s is suitable for most prints – Lower speeds are good for quality, however it increases print time.
• Fine-tune retraction pressures  To minimize stringing and oozing, retract at 5mm/s with 40mm/s retraction speed for direct drive extruders.
• Store filament properly  PLA absorbs moisture, so keep it in a cool, dry place to maintain print quality.
• Calibrate your extruder  Ensure accurate filament extrusion by properly calibrating steps per millimeter.
• Picking the appropriate infill percentage  15-20% infill is suitable for most prints but for structural elements higher values can be necessary.

Therefore, applying these methods, it is possible to obtain reproducible and good-quality PLA printed objects with few problems.

Pros and Cons of Using PLA for 3D Printing

Advantages of PLA

• PLA is highly popular in the 3D printing community for the following reasons:.
• Low warping  The low thermal expansion prevents distortion in printing.
• Good layer adhesion – Promotes stable, well-bonded prints.
• Low printing temperatures  save energy and decrease the wear on printer elements.
• Minimal odor  Emits little to no fumes, making it ideal for indoor use.
• Fast printing speeds  Can be printed at high speeds without significant quality loss.
• Extensive range of colors and surface finishes – Glossy, matte, translucent, and fluorescent (glow-in-the-dark) is available.
• Eco-friendly – Biodegradable under industrial composting conditions.

Due to these characteristics, PLA is perfect to be used in big prints, prototypes, and artistic work. Its small shrinkage enables flat prints with high accuracy without the need for a heated bed, thus saving energy and reducing equipment expenses.

Limitations of PLA and Solutions

Despite its benefits, PLA filament has some drawbacks:

❌ Low heat resistance (Glass transition temperature: 60-65°C)
🔹 Solution: If heat resistance is needed, consider annealing PLA or using high-temperature PLA blends.

❌ Brittle nature – PLA can snap under stress.
🔹 Solution: Use a higher infill percentage or opt for PLA+, which has added impact resistance.

❌ Limited outdoor durability – PLA filament degrades when exposed to UV light and moisture.
🔹 Solution: Apply a UV-resistant coating or use more weather-resistant alternatives like PETG or ASA.

❌ Difficult post-processing – PLA filament is harder to sand or smooth than materials like ABS.
🔹 Solution: Use filler primers before painting or experiment with chemical smoothing techniques.

Due to its simplicity, low cost, and flexibility, PLA is used in a broad range of industries.

1. Prototyping

PLA is a material of choice for engineers and designers, requiring a fast and inexpensive production of prototypes. It enables swift experimentation and iteration, such that design shall be testable and feasible for various material prior to making it into more persistent ones.

2. Education

A significant amount of institutions are embedding PLA filament in STEM courses, thereby providing students with an opportunity to work directly at hand with 3D printing. PLA’s low toxicity and biodegradability also relate to sustainability based educational programs.

3. Art and Design

Artists and designers work with PLA to produce sculptures, jewelry and decorative items. The availability of special PLA blends (e.g., wood-reinforced and metal-reinforced filaments) permits special texturing and surface finishes.

4. Medical Applications

PLA is commonly used in biocompatible medical devices, including:

• Custom prosthetics and braces
• Tissue engineering scaffolds
• Anatomical models for surgical training

These applications assist medical doctors and students to visualize complicated structures prior to real surgery.

5. Maker Community and DIY Projects

Hobbyists and makers rely on PLA for custom gadgets, household items, and replacement parts. Its low cost and ease of use makes it perfect for small projects.

6. Sustainable Packaging

Due to the trend toward more ecologic replacement, PLA filament is being found more and more for use in biodegradable packaging materials. In contrast to conventional plastics, PLA-based packaging naturally degrades under optimal conditions, minimizing environmental footprint.

PLA: A Sustainable Alternative to Conventional Plastics

By their biodegradability, Polylactic Acid (PLA) is distinguished of conventional plastics and serves as a more environmentally friendly alternative with a wide range of applications. In contrast with petroleum-derived plastics, which remain hundreds of years, PLA filament is fragmented by hydrolytic hydrolysis, in which water molecules break down its polymer chains into fragments of smaller unit molecules. All of these fragments are subsequently deconstructed by microorganisms, which ultimately convert to carbon dioxide, water, and biomass.

The Biodegradation Process of PLA

PLA undergoes decomposition in several key phases:

1. Hydrolysis  Water molecules attack the ester bonds within the PLA structure.
2. Fragmentation – The polymer degrades into oligomers and monomers.
3. Assimilation – Microorganisms metabolize these smaller molecules.
4. Mineralization  The last step, whereby CO₂, H₂O and biodegradable matter are released.

Industrial Composting and PLA Degradation

Accordingly, for PLA to be broken down efficiently PLA filament needs certain environments such as elevated temperature  55°C), humidity or microbial activity that are usually obtainable in industrial compost plants. Under such controlled conditions, PLA can biodegrade within 3 to 6 months.

By contrast, conventional plastics such as polyethylene (PE) and polypropylene (PP) can remain in the environment for centuries. However, it’s important to note that PLA does not break down easily in home composting systems or marine environments, as these lack the consistent high temperatures necessary for degradation. In landfills, PLA may degrade much slower, but still a faster rate than conventional plastics.

Carbon Footprint and Sustainability of PLA

Life cycle assessment (LCA) of PLA production showcases the winners and losers of the environment tradeoff, from raw material production to waste disposal. PLA is mainly made from starches such as corn or sugarcane and subjected to a series of multiphase steps:.

• Crop Cultivation  Requires land, water, fertilizers, and pesticides, potentially impacting biodiversity.
• Starch Extraction – Energy-demanding steps elude starch from plant biomass.
• Fermentation  Converts starch into lactic acid, generating CO₂ as a byproduct.
• Polymerization – Lactic acid monomers participate in energy-demanding processes to produce PLA.
• End-of-Life – PLA is industrial compostable, or in certain cases, mechanically recycled.

Comparing PLA with Petroleum-Based Plastics

The production of PLA filament is much more energy-efficient than fossil-fuel-based plastics. The energy consumption for PLA is reported to be 25-55% lower than that of conventional plastics (polyester terephthalate [PET] and polystyrene [PS]. This results in a reduced carbon footprint where PLA releases about 1.3 kg CO₂ per kg of material, and PET contains about 2.0 kg CO₂ per kg.

But the environmental effect of PLA is determined by many factors such as:.

• Feedstock Source  Using agricultural waste instead of dedicated crops can further reduce emissions.
• Energy Usage  Incorporating renewable energy in PLA manufacturing can dramatically improve sustainability.
• Agricultural Practices  Better sugarcane farming techniques and optimized fermentation methods can lower PLA’s environmental footprint.

To extract the full ecological advantage of PLA, the authors recommend the optimal sugarcane juice processing, improved energy recovery schemes and the minimized use of chemical inputs in the manufacturing process.

Final Thoughts: The Strengths and Weaknesses of PLA filament

Advantages of PLA filament

Biodegradable in industrial conditions – prevents long-term plastic pollution.

✔ Low warping tendency – Ensures consistent printing results.

Can be printed with great ease  Suitable for novice users of 3D printing.

✔ High-resolution detail – Produces smooth, accurate prints.

✔ Affordable – Widely available at a low cost.

Diverse aesthetic options  Comes in numerous colors, textures, and specialty blends.

Challenges of PLA filament

Low heat resistance – Softens at approximately 60-65 °C, not applicable to high-temperature applications.

🔹 Solution: Consider annealing PLA prints or using heat-resistant PLA blends.

Brittleness  PLA filament is prone to cracking under impact or stress.

🔹 Solution: Use higher infill percentages or blended PLA variants with enhanced durability.

Although PLA is an excellent material for environmentally aware end-users, functional constraints of PLA must be taken into account for selection of PLA filament in particular applications.