3D Printing of TPU, what you need to know
Cos'è il TPU?
It TPU (Termoplastic Polyurethane or Thermoplastic Polyurethane) is an elastomeric thermoplastic polymer belonging to the polyurethane family.
TPU is known for its flexibility, elasticity and tensile strength, important characteristics that make it a widespread material and also widely used in 3D printing for the production of flexible parts, resistant to thermal and mechanical stress
TPU is a thermoplastic material, which means it can be melted and printed with 3D printers at high temperatures.
Thanks to its high elasticity, TPU is used for the production of parts that require some flexibility, like the soles of shoes, the cable sheaths, cases for electronic devices, flexible hoses and much more.
TPU also has good resistance to chemicals and abrasions, making it an ideal material for industrial applications. Furthermore, TPU is available in different hardnesses called “Shore”, which means it can be used to produce parts with different hardness and flexibility properties.
How TPU is produced?
TPU is produced through a chemical reaction between an isocyanate and a polyol in the presence of a catalyst. During this reaction, the isocyanate and hydroxyl groups combine to form urethane bonds, creating an elastomeric thermoplastic polymer.
There are several variations of TPU, depending on the specific types of isocyanates and polyols used in production. In general, the polyols used in the production of TPU are polyesters or polyether, while isocyanates are usually aliphatic or aromatic.
The production process of TPU is very similar to that of the production of rigid polyurethanes, but with some key differences, such as the use of low molecular weight polyols and low reactivity isocyanates, which allows to obtain an elastomeric material.
Once produced, TPU can be used for a wide range of applications due to its flexibility properties, elasticity, resistance to abrasion and traction.
What are the Properties and Characteristics of TPU?
TPU has numerous properties and characteristics that make it a popular material for a wide range of applications.
Here are some of its main properties and characteristics:
1. Flexibility and elasticity: TPU is known for its high flexibility and elasticity, making it ideal for producing parts that require some flexibility, like the soles of shoes, flexible hoses and cable sheaths.
2. Tensile strength: TPU has good tensile strength, which makes it a resistant and durable material.
3. Abrasion resistance: TPU is abrasion resistant, which makes it ideal for industrial applications that require a certain resistance to wear.
4. Resistance to chemical agents: TPU is resistant to chemicals, making it an ideal material for applications where some resistance to chemicals is required.
5. Good adhesion: TPU has good adhesion to other materials, making it ideal for the production of composite parts.
6. Variable hardness: TPU is available in different Shore hardnesses, which means it can be used to produce parts with different hardness and flexibility properties.
7. Ease of processing: TPU is easy to work with and can be 3D printed, thermoformed, laminated and glued.
In general, TPU is a versatile and durable material that is used in a wide range of applications, from shoe soles to cable sheaths, up to industrial parts and medical applications.
Table in "SHORE" on the degree of hardness of the TPU
How to 3D Print TPU?
To 3D print with TPU, you can try following these steps:
Prepare your 3D model: use 3D modeling software to create or download a 3D model that you want to print.
Set up your 3D printer: make sure your printer is configured correctly to print with TPU. This means making sure the temperature and print speed are set correctly for this material.
TPU printing temperature depends on the type of 3D printer you are using and the specific print settings you have selected, but in general TPU requires a relatively low melting temperature compared to other 3D printing materials.
Generally, it is recommended to use an extrusion temperature between 200 e 230 degrees Celsius for TPU. However, It's important to run a series of print tests to find the best temperature settings for your 3D printer and your TPU filament. This way you can get the best possible print quality with your material of choice.
Furthermore, It's important to note that some 3D printers require slightly different extrusion temperatures for TPU. Always be sure to consult the manufacturer's instructions for your 3D printer and TPU filament to ensure high-quality printing.
Regarding the printing speed for TPU, to obtain the best quality we recommend using a printing speed between 20 and 40 mm/s.
However, It's important to note that print speed also depends on the type of 3D printer you're using and the other print settings you've selected.
TPU generally requires a slower printing speed than other 3D printing materials, since too high a print speed can cause problems such as low adhesion to the print bed, excessive heat buildup and excessive deformation of the material during printing.
To get the best print quality with TPU, we recommend running a series of print tests to find the ideal speed settings for your 3D printer and your TPU filament. This way you can get the best possible print quality with your material of choice.
You can now set up your 3D printer to print TPU, then install the filament into your 3D printer, and possibly also prepare the printing platform with an adhesive suitable for your bed which generally for optimal adhesion will need to be preheated to a temperature of around 75-80 degrees Celsius.
Once you have applied the correct settings to 3D print the TPU, Be sure to monitor your print carefully to avoid issues such as uneven adhesion to the print bed or excessive heat buildup.
Remove the print: once printing is complete, wait for the plate to cool completely and carefully remove your 3D object from the build platform.
Clean your 3D printer after each print to ensure it does not deteriorate and is ready for the next time you want to print with TPU.
Remember that 3D printing with TPU requires some specific precautions, such as using a direct extrusion print head, possibly it is necessary to check whether the use of printing supports capable of supporting the TPU during the printing of significant changes is also necessary.
Always follow your 3D printer manufacturer's instructions and in particular make sure to apply the 3D printing specifications of the TPU filament used. to always guarantee a high quality result.
What can be printed with TPU?
TPU is a flexible and resistant elastomeric material, making it ideal for producing parts that require some flexibility, resistance to abrasion and traction.
Here are some of the things that can be 3D printed with TPU:
1. Shoe soles: TPU is often used for the production of shoe soles, thanks to its flexibility and abrasion resistance.
2. Flexible hoses: TPU is used for the production of flexible hoses, such as those used in water or air management systems.
3. Cable sheaths: TPU is often used for the production of cable jackets, thanks to its flexibility and elasticity.
4. Cases for electronic devices: TPU is used to produce cases for electronic devices, come smartphone o tablet, thanks to its resistance to falls.
5. Protections for sports equipment: TPU is used to produce protection for sports equipment, like helmets, knee pads, elbow pads, thanks to its flexibility and impact resistance.
6. Prototypes: TPU is used for the production of prototypes, thanks to its ease of processing and its flexibility.
7. Bushings to absorb shocks and vibrations in motor vehicles, in particular, TPU is also used in various car suspension components such as shock absorbers, arms, end of stroke etc.
In general, TPU is used for the production of parts that require some flexibility, resistance to abrasion and traction, making it an ideal material for a wide range of applications.