If you’re looking to 3D print, you’re likely to come across PETG vs PLA. These widely used filaments have their own advantages and are ideal for specific applications. But how do you know which material is best for your project?
In this article, we’ll give you a clear comparison of PETG vs PLA filament. So that by the end of it, you’ll be able to select the best choice of filaments for your next product development project.
What is PLA Filament?
Polylactic acid or polylactide (PLA) is polyesters made from renewable biomass. These polyesters typically originate from fermented plants. For example, maize, cassava, corn, sugarcane, and sugar beet pulp.
First, the biomass undergoes bacterial fermentation, yielding lactic acid. The lactic acid is then converted to lactide. In this stage it undergoes ring-opening polymerization to form high molecular weight PLA. Which is essentially a high-molecular-weight, versatile thermoplastic.
After this process, the properties of the PLA's can be further altered. These alterations are primarily done by mixing it with plasticizers or nucleating agents.
PLA can be divided into two categories:
- PLA: The pure polymer. However, its properties can be adjusted by adding specific additives.
- PLA+: This variant includes additives. For example, it might have carbon fiber, wood fiber, or metal particles. These are added to modify the material's mechanical properties and improve attributes, such as its tensile strength or thermal conductivity.
PLA has a relatively low melting point, ranging from 190 to 220°C. It also has a glass transition temperature around 60°C and a tensile strength is at ~50 MPa. This is seen as high. But the material remains brittle with limited flexibility. Consequently, it has a poor resistance to heat and UV exposure and is highly moisture-sensitive and is ideal biodegradable products. These include medical devices, bottles, screws, pins, rods, and other items meant to last 6 to 12 months.
What is PETG Filament?
Polyethylene terephthalate glycol (PETG) is a thermoplastic polyester that comes from petroleum-based resources. As its name indicates, it is built on the foundation of a traditional PET. The addition of glycol modifies the material’s molecular structure, making PETG less prone to brittleness. It is also easier to process compared to standard PET.
The production involves:
1) Condensation polymerization of terephthalic acid (PTA)
2) Ethylene glycol (EG)
These additions reduce brittleness, improves flexibility, and ensures smoother performance for more demanding applications.
In general, PETG can be categorised into two main types:
- Standard PETG: Contains the base polymer with minimal additives.
- Modified PETG: Includes additives such as impact modifiers, UV stabilizers, or colorants to improve specific properties.
PETG has a melting point between 220–260°C. Its glass transition temperature (Tg) is around 90°C. As such it is more suitable for higher-temperature applications, compared to PLA. PETG offers a tensile strength of 45 MPa and has an elongation at break of about 35%, giving it better impact resistance and flexibility than PLA. It’s worth noting the material is resistant to moisture, chemicals, and UV exposure.
However, these benefits come with trade-offs. PETG’s has a higher printing temperature and is sensitive to precise temperature control. This can pose a challenge as improper handling may lead to issues like warping or stringing during 3D printing.
Quick Comparison Table of PLA vs PETG filament
|
Attribute |
PLA |
PETG |
|
Tensile Strength |
Moderate (~50) |
Moderate (~45) |
|
Flexibility |
Low (Elongation at break: ~2-6%) |
High (Elongation at break: ~35%) |
|
Temperature Resistance |
Low (up to 60°C) |
High (up to 90°C+) |
|
Ease of Printing |
Very easy |
Moderate |
|
Post-Processing |
Easy to sand/paint |
Hard to sand, limited painting |
|
Environmental Impact |
Biodegradable |
Recyclable but not biodegradable |
|
Cost |
Low |
Moderate |
|
Common Applications |
Prototypes, decorative items, short-term use |
Functional parts, mechanical components, outdoor use |
Which Should You Choose? PLA vs PETG
Choosing between PLA and PETG might seem daunting at first. In the end, it comes down to your specific needs.
Why You Should Choose PLA
PLA is a beginner-friendly option. In essence it means that it’s easy to print, affordable, and ideal for projects that don’t need to handle too much stress.
You could opt for this option if you:
- You’re new to 3D printing and want hassle-free printing.
- You desire a smooth, glossy finish for your decorative model or prototype.
- You want to sand or paint your prints.
- You are concerned about sustainability.
If your project doesn’t require high strength, flexibility, or heat resistance, PLA is likely the ideal choice.
Why You Should Choose PETG
PETG, on the other hand, shines when you need strength and flexibility. It’s more advanced to work with. But in return it offers durability.
- It has the strength and durability, ideal for parts that need to handle wear and tear.
- It can bend slightly without snapping, making it great for functional parts.
- Ability to withstand higher temperatures, up to 90°C or more.
- Chemical resistant and can handle moisture or mild chemicals.
That said, PETG requires careful printing. It’s not as easy to use as PLA.
Frequently Asked Questions (FAQs)
What Is the Difference Between PLA and PETG?
PLA is biodegradable, easier to print, and better for decorative parts. PETG is more durable, flexible, and heat-resistant.
Is PETG More Flexible Than PLA?
Yes, PETG is significantly more flexible and less brittle than PLA.
What Is PETG Good For?
Ideal for functional parts exposed to wear, heat, or moisture, like mechanical components or containers.
What Is the Difference Between PLA vs PETG Strength?
PETG is stronger, with better impact resistance and tensile strength.
PETG vs PLA Temperature Range?
PLA: 190 to 220°C. PETG: 220–260°C. (printing temperatures).
Conclusion: PETG vs PLA Made Simple
PLA and PETG are the most versatile and used filaments in 3D printing. Each of them has its own strengths and weaknesses. In this article we compared PETG vs PLA. PLA filaments stand out in its simplicity, affordability and sustainability. It is ideal for beginners and projects concerned about aesthetics. Meanwhile, PETG filaments shine in its strength and durability. Because of this, PETG can be used in applications demanding durability and resistance. Overall, the key of choice depends on your project’s needs.
Whether you're printing decorative prototypes or functional parts, Haizol Global can help with any service related to product development and manufacturing. Contact our consultants for free today to learn more how we can help your business.