3D Printing Info

Filament comparison

PA aramid vs TPU 85A

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

Aramid-fibre nylon guideTPU 85A guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PA aramid comparisonsMore TPU 85A comparisons
PA aramid vs TPU 85A — documented properties and sources
PropertyAramid-fibre nylonPATPU 85AFLEX
Market snapshot
Listing priceUSD/kg; dated snapshotsNot documented$89.89/kg median; $31.99–$106.05/kg across 6 dated product listings
Identity & Market
Base polymer / chemistryAramid-fibre reinforced polyamide[1]Soft thermoplastic polyurethane at 82–85 Shore A[2][3][4]
Densityg/cm³Not documented1.11 (BASF Ultrafuse 85A) to 1.19 (NinjaFlex 85A), ISO 1183 / ASTM D792[4][2]
Typical priceUSD/kgNot documented1 kg-equivalent spools span 32–106; the middle of the market is about 90[5][6][2]
Price range across brandsUSD/kgNot documented32–106 across brands; Siraya Tech Flex TPU 85A 32 at 1 kg, add:north TPU Pro Matte 85A 72, Recreus Filaflex 82A 90 at 500 g, Proto-pasta Clear Flexible TPU 90, 3DXTech 3DXFLEX 85A 96, NinjaTek NinjaFlex 106[7][5][6][8][2]
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[9][5]Available from several mainstream brands[5][7]
Spool sizes & diametersNot documented1.75, 2.85 and 3 mm; 0.5, 1 and 2 kg spools[5][7][2]
Typical applicationsNot documentedSoft-touch grips, seals, wearables and anything that must compress and rebound[2][3]
Printing Parameters
Nozzle temperature°CNot documented200–220 (BASF Ultrafuse 85A, 210 typical)[4]
Bed temperature°CNot documented40 (BASF Ultrafuse 85A)[4]
Enclosure / chamber requirement1–5Enclosure required (passive) — as for every nylon[1]Open frame is fine[4]
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]
Maximum volumetric flow (mm³/s; see test conditions)mm³/sNot documented1.2–3.2 at the 15–40 mm/s BASF specifies on a 0.4 mm nozzle at 0.2 mm layer[4]
Warping tendency1–5Not documentedNone[4]
Bed-adhesion difficulty1–5Not documentedSticks to anything — Recreus states its 82A grade has excellent bed adhesion without a heated bed or additives[3]
Stringing / oozing tendency1–5Not documentedHigh — drying plus tuning needed[12][11]
Overall printing difficulty1–5Not documentedAdvanced — enclosure, hardware upgrades, tuning; at this hardness the filament will not push through a Bowden tube[2][3]
Extruder requirementNot documentedDirect drive only. NinjaTek calls its 85A grade ideal for direct-drive extruders and Recreus specifies direct-drive printers for 82A; BASF caps print speed at 15–40 mm/s with a nozzle of 0.4 mm or larger[2][3][4]
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[13]Brass fine indefinitely[14]
Abrasiveness1–5Highly abrasive — fibre-reinforced nylon composite[13]Non-abrasive[14]
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[15]High — jams from moisture, heat creep or particles[12][11]
Heat-creep / jam sensitivity1–5Not documentedVery high — softens in the cold zone readily; soft filament buckles between the drive gear and the melt zone[11][2]
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[12]Moderate — NinjaTek measures 0.22 % in 24 h (ASTM D570) and BASF specifies a 70 °C dry for at least 5 h[2][4]
Equilibrium moisture content at ~50 % RH%Not documented0.22 after 24 h water immersion (NinjaFlex 85A, ASTM D570) — an immersion figure, not an equilibrium moisture content at 50 % RH[2]
Drying temperature & timeNot documented70 °C for at least 5 h in a hot-air dryer or vacuum oven (BASF)[4]
Symptoms when wetNot documentedBubbling and popping at the nozzle, stringing and a rough surface[12]
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; wet TPU prints with poor layer adhesion and weak, brittle layers[12]
Storage requirementNot documentedSealed with desiccant; often kept in a dryer during the print[12]
Mechanical Properties
Tensile strength (XY)MPaNot documented26 ultimate (NinjaFlex 85A, ASTM D638)[2]
Young's modulusMPaNot documented12 (NinjaFlex 85A, ASTM D638) — two orders of magnitude below any rigid filament; NinjaTek's 95A Cheetah reaches 26 by the same method[2][18]
Elongation at break%Not documented650 at break (Filaflex 82A) and 660 (NinjaFlex 85A); BASF measures 600 in XY and 320 in ZX[3][2][4]
Brittleness1–5Not documentedVery ductile — bends far before failing[2]
Hardness (scale-specific)Shore A / Shore D / RockwellNot documented29 Shore D / 85 Shore A (BASF Ultrafuse 85A, ISO 7619-1); 85 Shore A (NinjaFlex, ASTM D2240); 82 A nominal for Filaflex[2][4][3]
Creep resistance / sustained load1–5Not documentedPoor — no 85A creep test; a printed 95A TPU bar crept from 74.5 to 82.7 mm over 5 days at 1.25 kg, and softer grades creep more[19]
Fatigue / repeated-flex resistance1–5Not documentedExcellent — living hinges viable[11]
Elasticity / flexibility1–5Not documentedRubbery / highly elastic[2][3]
Z strength as % of XY%Not documented53 — BASF measures 320 % elongation at break in ZX against 600 % in XY[4]
Wear resistance & frictionNot documentedAbrasion 0.08 g mass loss over 10 000 cycles (NinjaFlex, ASTM D4060); 82 mm³ (BASF, ISO 4649)[2][4]
Thermal Properties
Melting point / Vicat°CNot documented216 melting (NinjaFlex 85A, 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[20]Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[20]
VOC emission rateµg/minUp to 180 caprolactam, the dominant VOC from nylon and the largest single-VOC rate in the study[20]Not documented
Ultrafine-particle emission rateparticles/min≈2 × 10⁸ median for nylon — low for particles despite the highest VOC mass measured[20]Not documented
Hazardous species emittedCaprolactam, at up to 180 µg/min from nylon filament[20]Not documented
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[20]Open a window / occasional ventilation[20]
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.[21]DMF, DMSO, NMP and THF dissolve TPU; acetone, MEK and cyclohexanone are partial solvents. All laboratory reagents.[22]
Softened or crazed byZinc chloride solutions stress-crack the nylon matrix, alcoholic calcium chloride dissolves it, mineral acids attack it.[21]Toluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[22]
Solvent welding & smoothing agentNone — nylon's only solvents (formic acid, phenol, HFIP) degrade the part, and the fibre blocks surface flow anyway.[21]None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[22]

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. NinjaFlex 85A Technical Specifications NinjaTek · 2026-08 · tds
  3. Filaflex 82A product page (Shore hardness and elongation) Recreus · 2026-08 · vendor
  4. Ultrafuse TPU 85A Technical Data Sheet (Version 3.0) BASF Forward AM · 2022-08 · tds
  5. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  6. Siraya Tech Flex TPU 85A Filament — product page Siraya Tech · 2026-08 · vendor
  7. Proto-pasta product catalogue Proto-pasta · 2026-08 · vendor
  8. add:north TPU Pro Matte 85A product page add:north · 2026-08 · vendor
  9. Polymaker product catalogue Polymaker · 2026-08 · vendor
  10. Flexible (TPE/TPU) — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  11. TPU — material basics Polymaker Wiki · 2026-08 · doc
  12. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  13. Fiberon PA6-CF20 Technical Data Sheet V1.1 Polymaker · 2024-12 · tds
  14. Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
  15. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 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. NinjaTek technical specs comparison chart (Cheetah, NinjaFlex, Armadillo, Alloy 910, Nylon 645) NinjaTek · 2026-08 · tds
  19. BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · test
  20. 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
  21. Ultramid Nylon Chemical Resistance guide (unmodified PA6 B27E and PA66 A27E) BASF · 2026-08 · tds
  22. Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds