PLA vs PETG: What are the differences

Material selection plays a huge role alongside printing proficiency when it comes to 3D prints. The right filament guarantees the best possible print quality, structural integrity, and compatibility with your intended application.
People often fail to realise the nuanced disparities between PETG and PLA filament and end up choosing the wrong one causing printing issues.

In this article on PLA vs PETG, we will depict the key difference between the two thermoplastics, their properties, advantages, and drawbacks. Moreover, we will also delve into the crucial factors based on which you can choose the best filament.

PLA filament

Definition and composition of PLA filament

Polylactic Acid or PLA is a biodegradable thermoplastic. Manufacturers use sugarcane or corn starch as materials for this filament. PLA is highly popular among 3D printing enthusiasts thanks to its eco-friendliness, low toxicity level, and printing ease.

PLA filaments are made of long chains of polymerized lactic acid molecules. It carries the same properties as old-style petroleum-based plastics though the filament is degradable. It is a key point when it comes to PLA vs PETG.

PLA is largely used in industries such as prototyping, education, aerospace, automotive, and packaging. People choose this filament over others because of its affordability, versatility, and eco-friendliness making it the most used 3d printing filament.

Properties and characteristics of PLA filament

Tetrahydrofuran, hot benzene, and dioxane are among the solvents in which PLA is soluble. Depending on the polymer type, the mechanical and physical properties can vary. You can choose from a very crystalline polymer to an amorphous glassy polymer.

General characteristics

1. Low toxicity
2. Easy to print
3. Uses renewable raw material
4. Bio-climactic
5. Vibrant colours

General properties

Property	Value
Rate of shrinkage	0.37 to 0.41 per cent
Tensile Strength	50 MPa
Heat Deflection Temp	52 °C or 126 °F
Density	1.24 g/cm³
Flexural Strength	80 MPa
Impact Strength	96.1

Advantages of PLA filament

Compared to other materials, PLA has several benefits that make the filament stand out, including:

• PLA is eco-friendly If you follow the right conditions while disposing of it.
• Easy to print 3D objects
• Beginner friendly
• Perfectly safe for printing applications such as medical apparatus and food containers
• A wide range of vibrant colours makes the prints more alluring.
• With the use of dichloromethane or methylene chloride, it is possible to solvent-weld PLA.

Common applications of PLA filament

As mentioned, PLA is very popular in many industries because of its printing ease and compatibility with a variety of 3D printers. Its consistent printing properties allow rapid prototyping and the creation of consumer goods such as household items.

FDA-approved PLA is extensively used in the medical industry to create non-implantable prototypes and surgical models for training. The Filament is also favoured in creative projects like designing mock-ups, jewellery, and artwork as well as printing models and scales in the architectural field.

If you are confused between PLA vs PETG, know that hobbyists and DIY enthusiasts prefer PLA while working on creative works.

Limitations and drawbacks of PLA filament

To understand the core differences and choose the right filament in terms of PLA vs PETG, you need to be aware of the limitations too. Some of the drawbacks of PLA include:

• PLA has low heat resistance due to its lower glass transition temperature.
• PLA tends to be brittle compared to other filaments affecting its durability and strength.
• PLA is a hygroscopic thermoplastic that easily soaks up moisture from the environment which can degrade the print quality and mechanical properties.
• With PLA, people often find machine processing tough.

PETG filament

Definition and composition of PETG filament

PETG is a recyclable industrial-grade thermoplastic that blends the best attributes of PLA and ABS. The filament is as strong and durable as ABS filament and user-friendly like PLA.

Polyethylene Terephthalate Glycol or PETG filament is made of thermoplastic polymer chains sourced from terephthalic acid and ethylene glycol. PETG is used for printing strong and durable objects with great impact resistance.

PETG is a versatile 3D printing filament that can be used in printing a wide range of applications from food containers to machine guards. The filament is suited for both expert and newbie users.

Properties and characteristics of PETG filament

• Print temperature 220-250°C
• Has a low shrinkage level reducing the risk of warping and better dimensional accuracy.
• Perfect for printing functional prototypes because of its high impact resistance and durability.
• Versatile with high tensile strength which lowers the chances of breakage while printing.
• Has excellent chemical resistance making it food-safe.
• PETG is a translucent filament suited for printing glossy and aesthetic objects.
• Has good thermal stability

Advantages of PETG filament

If we compare based on PLA vs PETG, some of the advantages of PETG include:

• Better resistance in shock loading because of its higher elasticity.
• PETG has superior chemical stability and impact strength than PLA.
• PETG is better suited for resisting abrasion due to its higher hardness
• It is an odorless nontoxic 3D printing filament.
• Since the filament is transparent, it is easier to colour than PLA.

Common applications of PETG filament

PETG filaments are largely used in creating applications that need to be transparent, durable, and have good chemical resistance. Some of its common applications include but are not limited to:

• Mechanical components
• Accessories such as cosplay costume
• Planters
• Functional prototypes
• Educational models
• Display cases
• Food containers
• Drinkware
• Medical Apparatus
• Outdoor signage

Limitations and drawbacks of PETG filament

• Post-processing can be difficult.
• Softer exterior
• Prone to humidity and dampness
• Requires high print temperature
• Susceptible to stringing and oozing.

Key differences between PLA and PETG filaments

If you want to print top-notch 3D prints, it’s crucial to be able to select the right material first. Understanding the core difference between PLA vs PETG will ensure you know which filament will best suit your cause. Some of the key differences include:

Material composition

Renewable resources such as sugarcane, potato, or corn starch are used as raw materials in making PLA on the other hand ethylene glycol and terephthalic acid are used as raw materials for PETG.

Printing temperature and settings

The risk of warping is minimal when printing with PLA due to its lower printing temperature which usually ranges from 180-220°C. PETG is prone to oozing and stringing because of its high print temperature ranging from 220-250°C.

Strength and durability

Although PLA provides decent strength, the filament can be brittle. PETG is preferred because of its strength, and durability sourced from ethylene glycol and terephthalic.

Flexibility and impact resistance

PETG is great for printing functional parts due to its excellent impact resistance and flexibility whilst PLA is rather less flexible and rigid.

Surface finish and post-processing requirements

PLA comes with vibrant colors creating shiny prints and requires little post-processing. PETG needs proper post-processing techniques like sanding to smooth the exterior of the print.

Environmental considerations

PLA is eco-friendly because it uses sustainable resources as raw materials thus it is biodegradable under the right conditions. On the contrary, PETG is non-biodegradable though it is recyclable. So, if we consider the environmental impact, PLA no doubt is a better option.

Choosing between PLA and PETG

If you are someone who is new to 3D printing and cannot decide between PLA vs PETG, remember to consider the following points:

Factors to consider when selecting filament for 3D printing projects

1. Toughness
2. Durability
3. Chemical Resistance
4. Appearance
5. Impact Resistance
6. Environmental Impact

Comparison of PLA and PETG based on specific printing requirements

If your designs are simple, made for short-term use, and quick disposal, PLA would be the right choice. PLA doesn’t warp easily, prints at lower temperatures, good for details and easy to print with.
PETG is a little challenging because of its higher temperature requirement. So, this might not be the option you should go for as a newbie.
But if you want to print applications that are strong and durable, and demand better structural integrity and resilience such as functional parts, PETG is the right alternative. The filament is good for printing translucent and intricate models.

Personal preferences and project considerations

To print clear, strong, and aesthetic objects, opt for PETG. For printing simple models with better detailing, choose PLA. Both filaments have their pros and cons. Your choice should be based on the unique requirements of your project and your level of commitment to environmental considerations.

Frequently asked question

Is PETG really better than PLA?

In PLA vs PETG, the better filament alternative mainly depends on the specific requirement of the project. If your print needs to be flexible, strong, and durable with better impact resistance PETG sure is the best option.

What are the disadvantages of PETG?

Industry-grade PETG is more popular among 3D print experts although similar to other filaments it has a few disadvantages. It needs a high printing temperature to print which can lead to filament oozing and stringing. People who are new to 3D printing find it hard to work with because of its high melting point.

How can you tell PLA from PETG?

PLA vs PETG, to find the differences all you have to do is observe their printing characteristics and physical properties. 3D models printed with PLA tend to have a glossy finish though it is more brittle and rigid than PETG.
PETG filament is stronger, more versatile, and provides a matte finish to the prints although requires a higher print temperature than PLA.

What is the difference between PLA, ABS, and PETG?

ABS, PETG, and PLA are 3D printing filaments with varying print properties. ABS is known for impact resistance and strength, PETG for transparency and durability, and PLA for its eco-friendliness shiny finish, and printing ease.