PET is a thermoplastic from the polyester family and one of the most important thermoplastics due to the amount produced. The PETG filament is a modified version of PET and is also known as co-polyester. This improvement, which is necessary for 3D printing, is achieved by adding a second glycol. This makes it more durable, more impact-resistant and does not become brittle and fragile even through regular heating.
The PETG filament is very thermally deformable. Both the print image and the layer adhesion are very good. Elements printed from PETG can even be sterilized and are therefore also used in medical technology. In addition to its high resistance and optimal mechanical properties, PETG is chemical-resistant, flame-retardant and certified as a food-safe polymer. It is therefore used both for processing and for packaging food, but also in the pharmaceutical sector. In addition, this material is 100% recyclable. PETG is even said to combine the advantages of ABS (temperature resistance, durability and strength) and PLA (easy to use) in one filament.
Processing parameters:
| Extrusion temperature: | 215 °C |
| Platform temperature: | 60 °C – 80 °C |
| Printing surface: | Kapton |
As a rule, the PET filament is the glycol-modified variant, PETG. The added glycol molecule prevents the otherwise "partially crystalline" plastic from crystallizing. This makes it more ductile and allows it to be processed at a lower temperature. In this way, transparent filaments can also be produced.
PETG is tougher than most other filaments and tends to draw thin threads, so-called “angel hair”, after it has been removed. To avoid this effect, it is advisable to increase the "Retraction Distance", and the "X / Y Axis Movement Speed" should be increased in order to tear off these threads as soon as they are stopped.
PETG can be welded and screwed with or without an “inset”. Due to its high chemical resistance, PETG can only be glued with urethane-based and cyanoacrylate-based (super glue) adhesives. When machining, it must be ensured that the workpiece does not heat up too much, as otherwise the tool can stick together with melted plastic and damage the component.
Due to its chemical resistance, PETG cannot be painted or varnished, therefore components that are to have a certain color should be made directly with filaments of this color.
Resistant to weak acids, alkaline solutions, oils, fats, aliphatic and aromatic hydrocarbons and carbon tetrachloride.
It is not resistant to strong acids and alkaline solutions, phenol and long-term use in hot water above 70 ° C.
The maximum operating temperature of PETG is 70 ° C
PETG combines the ease of use of PLA with almost equally good mechanical and thermal properties as ABS. In addition, PETG is chemical-resistant, food-safe and flame-retardant. Due to the possibility of sterilizing elements printed from PETG, these are also used in medical technology.
In addition, PETG is often used to produce demonstration objects, for example in architecture, since the good thermal deformability, the good layer adhesion and the good optical properties of the material simplify the production of aesthetically pleasing prototypes.
Since the "polymer chains" are hardly damaged by repeated melting (within reasonable temperatures) and mechanical shredding of PETG, the plastic is 100% recyclable.