All You Need to Know About PETG for 3D Printing

PETG, or polyethylene terephthalate glycol, is a thermoplastic that is one of the most widely used polymers in additive manufacturing. Notably, it is a popular choice for filaments and fused deposition modeling because it combines both the simplicity of PLA 3D printing and the strength of ABS. It is an amorphous plastic, which can be 100% recyclable, with the same chemical composition as polyethylene terephthalate, better known by its acronym PET. To better under the material, the following guide outlines the characteristics of PETG, what you need to know for 3D printing with it, its main applications and manufacturers.

Production and Characteristics of PETG

To understand PETG, it’s important first to look at PET itself. PET is a well-known material in the industry, estimated to grow from USD 52.94 billion in 2024 to USD 109.63 billion by 2032, because it has been used in bottle manufacturing and packaging since the 1990s, replacing PVC. It also allows the production of synthetic fibers for clothing. However, it is not common to use pure PET in 3D printing. Rather, glycol (G) is added to PET at a molecular level, allowing the material to have greater strength and durability while making it more flexible.

Photo Credits: Thad Zajdowicz, CC0, via Wikimedia Commons

PETG is therefore a copolymer, combining the properties of PET and glycol. The addition of glycol reduces overheating issues with PET (which prevents it from being used for additive manufacturing as it is) as well as reduces its brittleness. Its hardness, impact and chemical resistance, transparency and ductility are among the main characteristics of PETG. It is an easily extruded material with good thermal stability, particularly appreciated for its compatibility with food.