3D Printing Info

Filament comparison

PA aramid vs TPU soft

Compare printing settings, strength, heat resistance, dated prices and sources.

Aramid-fibre nylon guideSoft TPU (below 85A) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PA aramid comparisonsMore TPU soft comparisons
PA aramid vs TPU soft — documented properties and sources
PropertyAramid-fibre nylonPASoft TPU (below 85A)FLEX
Market snapshot
Listing priceUSD/kg; dated snapshotsNot documented$114.04/kg median; $109.80–$122.27/kg across 4 dated product listings
Identity & Market
Base polymer / chemistryAramid-fibre reinforced polyamide[1]Very soft thermoplastic elastomers below 85 Shore A. Fiberlogy's FiberFlex 30D measures 81 Shore A, the softest grade with a published datasheet found here[2]
Densityg/cm³Not documented1.07 (Fiberlogy FiberFlex 30D, ISO 1183)[2]
Typical priceUSD/kgNot documented1 kg-equivalent spools cluster near 115[3][4][5]
Price range across brandsUSD/kgNot documented110–122 at 1 kg-equivalent; Recreus 70A 110 and 60A 116 at 500 g, NinjaTek Edge 83A 112, NinjaTek Chinchilla 75A 122; the Recreus 3 kg spools fall to 70–73[3][5][4]
Market availability1–5Special order, 1–2 makers worldwide — no aramid-filled nylon filament was found in any catalogue searched; the aramid filaments that do exist in the retail market use an ASA matrix[6][7]Niche, a handful of specialist brands[2][8][3]
Spool sizes & diametersNot documented1.75, 2.85 and 3 mm; 0.5, 0.85, 1, 2 and 3 kg spools[2][3][9][4]
Typical applicationsNot documentedHighly compliant seals, soft grips and prosthetic liners[2]
Printing Parameters
Bed temperature°CNot documented50–70 (Fiberlogy FiberFlex 30D)[2]
Enclosure / chamber requirement1–5Enclosure required (passive) — as for every nylon[1]Open frame is fine[2]
Bed surface & adhesion aidNot documentedPEI sheet or painter's tape; Polymaker warns TPU can over-stick and advises a glue stick as a release agent[10][11]
Overall printing difficulty1–5Not documentedExpert / industrial hardware only — below 85 Shore A the filament buckles in almost any feed path that is not a short, constrained direct drive[9][11]
Extruder requirementNot documentedDirect drive only, with a constrained filament path; Bowden is not viable at this hardness[9][8]
Hardware Wear & Reliability
Nozzle hardness required1–4Hardened steel required — no aramid-filled nylon datasheet was obtainable; Polymaker measures about 9 h of brass nozzle life on its fibre-filled nylons[12]Brass fine indefinitely[13]
Abrasiveness1–5Highly abrasive — fibre-reinforced nylon composite[12]Non-abrasive[13]
Nozzle clog risk1–5High — jams from moisture, heat creep or particles; nylon already needs a drybox and Prusa names kevlar among the fibres that raise nozzle-clogging risk[14]High — jams from moisture, heat creep or particles; below 85 Shore A the filament buckles and compresses, and Simplify3D warns that raised feed rates most likely end in a jam[10][11][15]
Heat-creep / jam sensitivity1–5Not documentedVery high — softens in the cold zone readily[11]
Hotend requirementNot documentedNo special hot-end required, but a direct-drive extruder is (Simplify3D)[10]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Very high (>2 %) — the polyamide matrix governs uptake[15]Moderate[15]
Symptoms when wetNot documentedBubbling and popping at the nozzle, stringing and a rough surface[15]
Effect of moisture on strengthPolymaker's printed dry-versus-wet blocks for its CoPA nylon show what conditioning does to the family: tensile 78.0 → 34.3 MPa and modulus 2703 → 724 MPa, with notched Charpy rising 6.9 → 27.7 kJ/m². Fibre reinforcement reduces but does not remove the effect[16][17]Polymaker groups TPU with the highly hygroscopic materials; no dry-versus-conditioned figures are published[15]
Storage requirementNot documentedSealed with desiccant; often kept in a dryer during the print[15]
Mechanical Properties
Elongation at break%Not documented870 at break (Fiberlogy FiberFlex 30D, ISO 527) — the highest elongation in the dataset[2]
Brittleness1–5Not documentedVery ductile — bends far before failing[2]
Hardness (scale-specific)Shore A / Shore D / RockwellNot documented81 Shore A and 30 Shore D (Fiberlogy FiberFlex 30D, ISO 7619)[2]
Creep resistance / sustained load1–5Not documentedPoor — no creep test at this hardness; a printed 95A TPU bar crept from 74.5 to 82.7 mm over 5 days at 1.25 kg[18]
Fatigue / repeated-flex resistance1–5Not documentedExcellent — living hinges viable[11]
Elasticity / flexibility1–5Not documentedRubbery / highly elastic[2]
Wear resistance & frictionNot documentedTear strength 95 kN/m (Fiberlogy FiberFlex 30D, ISO 34-1)[2]
Thermal Properties
Melting point / Vicat°CNot documented170 melting (Fiberlogy FiberFlex 30D, DSC)[2]
Environment & Chemical
UV resistance1–5Not documentedGood — years with some colour shift; Polymaker lists UV exposure among the conditions TPU withstands[11]
Chemical resistanceNot documentedWithstands industrial solvents and UV exposure (Polymaker)[11]
Food contactNot documentedNot food safe without specific certification (Polymaker)[11]
Biodegradability / compostabilityNot documentedNot biodegradable[11]
RecyclabilityNot documentedNot accepted in household plastic collection[11]
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[19]Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[19]
VOC emission rateµg/minUp to 180 caprolactam, the dominant VOC from nylon and the largest single-VOC rate in the study[19]Not documented
Ultrafine-particle emission rateparticles/min≈2 × 10⁸ median for nylon — low for particles despite the highest VOC mass measured[19]Not documented
Hazardous species emittedCaprolactam, at up to 180 µg/min from nylon filament[19]Not documented
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[19]Open a window / occasional ventilation[19]
Post-Processing
Sanding & machiningNot documentedDifficult to sand or smooth; Polymaker limits post-processing to trimming or tumbling[11]
Gluing & solvent weldingNot documentedCyanoacrylate bonds TPU; no common solvent welds it[11]
Vapour / chemical smoothingNot documentedNo practical vapour smoothing[11]
Support material pairingNot documentedPolymaker warns TPU supports are often very difficult to remove[11]
Solvents & Solubility
Soluble inFormic acid, phenol, m-cresol and hexafluoroisopropanol dissolve the matrix at 23 °C, leaving the fibre; laboratory reagents.[20]DMF, DMSO, NMP and THF dissolve TPU; acetone, MEK and cyclohexanone are partial solvents. All laboratory reagents.[21]
Softened or crazed byZinc chloride solutions stress-crack the nylon matrix, alcoholic calcium chloride dissolves it, mineral acids attack it.[20]Toluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[21]
Solvent welding & smoothing agentNone — nylon's only solvents (formic acid, phenol, HFIP) degrade the part, and the fibre blocks surface flow anyway.[20]None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[21]

Material entries describe families or representative grades, not an interchangeable specification for every spool. Test methods, orientations and conditions may differ. Unknown values are marked “Not documented”. Prices and source dates remain historical snapshots; check the linked guide for product details. Differences highlight text, not a universal winner.

Sources for this comparison

  1. PA (Nylon) — material basics Polymaker Wiki · 2026-08 · doc
  2. FiberFlex 30D Technical Data Sheet Fiberlogy · 2026-08 · tds
  3. Recreus product catalogue Recreus · 2026-08 · vendor
  4. Chinchilla product page — print guidelines, spool sizes and price NinjaTek · 2026-08 · vendor
  5. NinjaFlex Edge product page — durometer, print guidelines and price NinjaTek · 2026-08 · vendor
  6. Polymaker product catalogue Polymaker · 2026-08 · vendor
  7. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  8. Filaflex 82A product page (Shore hardness and elongation) Recreus · 2026-08 · vendor
  9. NinjaFlex 85A Technical Specifications NinjaTek · 2026-08 · tds
  10. Flexible (TPE/TPU) — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  11. TPU — material basics Polymaker Wiki · 2026-08 · doc
  12. Fiberon PA6-CF20 Technical Data Sheet V1.1 Polymaker · 2024-12 · tds
  13. Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
  14. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  15. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  16. PolyMide CoPA Technical Data Sheet V5.4 (dry and wet status blocks) Polymaker · 2024-11 · tds
  17. Moisture Conditioning — effect on printed nylon properties Polymaker Wiki · 2026-08 · doc
  18. BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · test
  19. Emissions of Ultrafine Particles and Volatile Organic Compounds from Commercially Available Desktop Three-Dimensional Printers with Multiple Filaments (Azimi et al.) Environmental Science & Technology 50(3) 1260-1268 · 2016-01 · paper
  20. Ultramid Nylon Chemical Resistance guide (unmodified PA6 B27E and PA66 A27E) BASF · 2026-08 · tds
  21. Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds