Polypropylene (PP) is a popular semi-rigid polymer material used to produce many common consumer products due to its superb mechanical properties. Suitable for a variety of applications, examples of everyday use cases can be found in the form of squeezable bottles, flip-top mint containers, car bumpers, toys, and so much more. Positive features associated with polypropylene include its robust resistance to chemicals, fatigue, high-temperature, and impact. This thermoplastic material is made up of hydrophobic molecules (molecules physically resistant to water), making it ideal for products that heavily rely on protection from moisture. With these qualities in mind, its no wonder polypropylene has caught the attention of 3D printing enthusiasts for prototyping purposes and even ready-to-use functional parts.

Polypropylene, polypropylene blends, and OBC filament are fantastic materials to produce prototypes that are durable and functional.
Polypropylene, polypropylene blends, and OBC filament are fantastic materials to produce prototypes that are durable and functional.

TABLE OF CONTENTS

POLYPROPYLENE AS A 3D PRINTER FILAMENT

While not as commonly available as filaments such as PLA, ABS or PETG, polypropylene is slowly expanding its variety and availability in the market, and becoming more affordable for consumers. Hobbyists can expand their printing options as PP is a great practical option for producing prototypes that are lightweight, have water-tight tolerances, and are extremely durable. You will find that these qualities make this material especially ideal for prototyping household plastic containers. While this thermoplastic is technically both safe for microwaves and food contact, we do NOT recommend using prints made with Fused Deposition Modeling (FDM) 3D printers to store consumable food and liquids due to the porous nature of FDM 3D printing and possible cross-contamination when extruding this filament out of hardware that has not been labeled food-safe. Nonetheless, polypropylene is still a fantastic option for producing prototypes such as mechanical parts and containers with living hinges to store physical objects and liquids not intended for consumption.

Have a product idea that will be made out of polypropylene? Produce your prototypes with its end-use material right from your workspace.
Have a product idea that will be made out of polypropylene? Produce your prototypes with its end-use material right from your workspace.

3D PRINTING WITH POLYPROPYLENE

Producing parts with this material admittedly require a bit more finetuning compared to other filaments such as the fan-favorite PLA. That's where this handy how-to succeed guide comes in! All the tips and tricks we've uncovered from MatterHackers' engineers can be found here, so any hobbyist interested in expanding their 3D printing options can increase their chances of success. One crucial thing makers should be aware of is that this thermoplastic has a semi-crystalline structure that causes it to potentially warp and shrink upon cooling. Users must pay closer attention to settings that they may not normally consider in comparison to standard filaments like PLA. To avoid warping and shrinkage, check out the tips below on how to successfully produce polypropylene prints.

CHECKLIST FOR SUCCESS: USE THE RIGHT TOOLS

The first key to success is making sure you have the right tools. That means having the right 3D printer and accessories. With polypropylene, only a couple of upgrades are recommended if they do not already come stock with your machine. FDM printers that have the electrical hardware to print with polypropylene include (but are not limited to) the Pulse 3D Printer, Raise3D Pro2, LulzBot TAZ 6, and Ultimaker S5.

Here at MatterHackers, we carry a wide variety of 3D printers that are ready to print advanced materials right out of the box.
Here at MatterHackers, we carry a wide variety of 3D printers that are ready to print advanced materials right out of the box.

Not sure if your 3D printer can safely extrude polypropylene? See if your 3D printer meets the following recommendations listed below.

HOTEND RECOMMENDATIONS

  • If printing a polypropylene with no special blends of other polymers and/or fibers (ex: SmartMaterials Polypropylene, Ultimaker Polypropylene), no special hotend is necessary.
  • If printing a polypropylene with a special blend of abrasive fibers (ex: X-Strand or BASF's Black PPGF [Polypropylene Glass Fiber] 30), a hotend that safely operates at temperatures of up to 300°C is highly recommended.
    • Universal hotends we recommend for this capability include (but are not limited to) E3D's V6 All-Metal Hotend, Slice Engineering's Mosquito All-Metal Hotend, and Micro-Swiss All-Metal Hotend.
    • An abrasive resistant nozzle is highly recommended when printing with abrasive fibers such as carbon and glass. These materials will wear out non-abrasive nozzles quickly, which will cause inconsistent extrusions during the printing process.
      • Abrasive resistant nozzles we recommend include (but are not limited to) Olsson Ruby Nozzles, Nozzle X, and any hardened steel or vanadium nozzles.
Whether you need a hotend that prints at 250°C or 300°C, MatterHackers has a variety of reliable extruder options that cater to your specific print needs.
Whether you need a hotend that prints at 250°C or 300°C, MatterHackers has a variety of reliable extruder options that cater to your specific print needs.
  • A heated bed that can safely operate at temperatures of up to 100°C is required.
  • LayerLock Build Surface for Polypropylene is the build surface we've seen produce the most consistent, successful results. Designed to succeed with polypropylene, certain polypropylene blends, and OBC filament, LayerLock Build Surface sheets provide the strong adhesion necessary to keep prints from warping. We highly recommend LayerLock Build Surface as it is available in medium to large sheets that can be cut to size for your print bed.
    • Packing tape is a possible alternative you can find around the house and in most stores. However, please note that it does require multiple strips of tape that must be carefully laid down (no creases or air bubbles), must be replaced more frequently, and may come with a few limitations (depending on what type of filament you are printing with). Also, confirm that the packing tape is made out of polypropylene as any other packing tape will not work.
Achieve the strong bed adhesion you need to succeed with polypropylene using LayerLock Build Surface and bed adhesion solutions for PP.
Achieve the strong bed adhesion you need to succeed with polypropylene using LayerLock Build Surface and bed adhesion solutions for PP.

ENCLOSURE RECOMMENDATIONS

  • Only required if printing in an area that is cold or where the temperature is inconsistent. View the wide variety of 3D printer enclosures available here.
Enclosures are fantastic 3D printer accessories for maintaining consistent, warm temperatures, which is critical when producing parts out of advanced materials in a cold or windy environment.
Enclosures are fantastic 3D printer accessories for maintaining consistent, warm temperatures, which is critical when producing parts out of advanced materials in a cold or windy environment.

HOW TO AVOID WARPING AND SHRINKAGE

Filaments that warp and/or shrink during 3D printing are nothing new among the current line of thermoplastics available on the market for both professionals and everyday hobbyists. Each type of material has its own special set of print settings and conditions it needs to succeed such as flexibles (TPU, TPE) benefiting from a PrintDry for quality print results and nylon/nylon-based materials like NylonX and NylonG heavily benefiting from both a PrintDry and LayerLock Garolite Build Surface for maximum print success. For polypropylene, a LayerLock Build Surface and polypropylene bed adhesion solution will maximize your success when 3D printing with this material. Depending on the temperature conditions of your workspace, an enclosure may also be recommended.

Whether it's PP, PPFG, or OBC filament, LayerLock Build Surface for Polypropylene will provide the bed adhesion necessary to prevent warping.
Whether it's PP, PPFG, or OBC filament, LayerLock Build Surface for Polypropylene will provide the bed adhesion necessary to prevent warping.

Achieving a strong bond between the first layer of your print and the heated bed's build surface is crucial for successfully avoiding warping. Like other filaments, printing too close can cause your part to stick too well to the bed and printing too high can lead to the material not sticking. What steps can you take to get that ideal first layer?

  1. Choose the right build surface.
  2. Level your bed.
  3. Set your nozzle at the appropriate height.

LayerLock Build Surface for Polypropylene has provided the most consistent results based on the continuous testing our engineers have been performing for months. Polypropylene has a strong tendency to warp as it tends to be extremely limited to what it likes to stick to and be sensitive to temperature. This thermoplastic loves sticking to our LayerLock Build Surface so you can rest easy knowing that first layer will stay firmly adhered to the build surface during the entire duration of the print. For easy removal post-printing, we recommend combining LayerLock with a bed adhesion solution specifically designed for polypropylene before the start of your print.

A successful first layer is necessary for an overall successful print. Make sure to use the right build surface that is compatible with polypropylene.
A successful first layer is necessary for an overall successful print. Make sure to use the right build surface that is compatible with polypropylene.

Before you start printing on any new bed surface, always remember to level your bed and calibrate your nozzle height to adjust for the print bed's height difference. With LayerLock Build Surface, it is essential to achieve the correct layer height because extruding too low may cause your print to fuse to the bed surface. When adjusting layer height, we always recommend starting higher than you normally would because that prevents the possibility of having your print fuse to the bed. A great starting point would be beginning a test print at a 1mm height away from the bed surface and working your way down. Optimal nozzle height is achieved when you see the filament extruded on the bed with a width of about 1 mm.

When finding the right distance between the nozzle and print bed during polypropylene extrusion, we suggest baby stepping on a test print to safely achieve that ideal layer height.
When finding the right distance between the nozzle and print bed during polypropylene extrusion, we suggest baby-stepping on a test print to safely achieve that ideal layer height.

As for shrinkage during 3D printing, that shouldn't be an issue when following our recommended print settings below on a LayerLock Build Surface for Polypropylene in a room with consistent room temperature. Our engineers have been performing these tests on our open-frame Pulse 3D Printers and have been successfully producing polypropylene parts! However, if you are limited to printing in a room below 70°C or an area with air conditioning, we highly recommend using a 3D printer enclosure to ensure your parts are being produced in a consistently warm environment. Cold air can easily cause your parts to cool too fast during printing which can lead to cracks in your prints, leaving them unusable in the end. If you don't have an enclosure and are not located in a consistently warm environment, check out our catalog of 3D printer enclosures and enclosure kits. Follow our recommended settings below with our recommended 3D printer accessories and you will be closer to polypropylene 3D printing success!

Need a 3D printer that prints polypropylene? Check out our Pulse XE 3D Printer we used to successfully achieve consistent results.
Need a 3D printer that prints polypropylene? Check out our Pulse XE 3D Printer we used to successfully achieve consistent results.

READY, SET, PRINT!

We hope these tips help you succeed with 3D printing polypropylene! With this thermoplastic found in many common household products, PP is the perfect end-use material for prototyping straight from your workbench. If you have any further questions, feel free to hop on our forum filled with helpful posts and fellow enthusiasts working together to create a smooth, enjoyable 3D printing experience.

Happy Printing!

Successfully produce functional end use products with LayerLock Build Surface for Polypropylene.
Successfully produce functional end-use products with LayerLock Build Surface for Polypropylene.