PPA vs TPU
Compare PPA and TPU filaments side-by-side so you can pick the right one for your 3D printing project.
PPA vs TPU: PPA is known for semi-aromatic nylon: aromatic rings in the backbone push..., while TPU is known for excellent layer adhesion. TPU is easier to print; PPA prints at higher nozzle temperatures (280-310°C vs 200-240°C). Choose PPA for semi-aromatic nylon: aromatic rings in the backbone push..., or TPU for excellent layer adhesion.
Key differences at a glance
PPA
CPolyphthalamide
Semi-aromatic nylon: aromatic rings in the backbone push Tg to ~130C and the melting point to ~300C
TPU
SThermoplastic Polyurethane
Excellent layer adhesion; extremely impact resistant; highly durable
Detailed Comparison
Green marks the generally easier or more forgiving option in that row, based on tier, enclosure needs, and moisture sensitivity. It is not always the better choice for a specific job, so weigh it against what your project actually needs.
Strengths Comparison
PPA Strengths
- Semi-aromatic nylon: aromatic rings in the backbone push Tg to ~130C and the melting point to ~300C
- Holds strength, stiffness and dimensions at temperatures where PA6, ABS and PETG soften
- Strong resistance to oils, greases, fuels and industrial chemicals
- Absorbs far less moisture than PA6, so properties stay consistent in humid air
TPU Strengths
- Excellent layer adhesion; extremely impact resistant; highly durable
- Great for combat robots, tactical/rough-use parts
- Rubber-like parts (gaskets, grips, bumpers, wheels)
Considerations
PPA Caveats
- Needs a ~300C-capable all-metal hotend and an enclosure, which rules out most desktop printers
- Unfilled PPA is usually the wrong buy: most commercial 3D printing PPA is sold carbon- or glass-filled
- Expensive, and demanding drying (roughly 100-140C) before every print
TPU Caveats
- Slow printing; retraction can cause jams (especially in Bowden setups)
- Stringing is common
- Very moisture sensitive; wet TPU prints poorly