3D Printing Info

Filament comparison

PEI 9085 vs TPU 85A

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

PEI (ULTEM 9085) guideTPU 85A guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PEI 9085 comparisonsMore TPU 85A comparisons
PEI 9085 vs TPU 85A — documented properties and sources
PropertyPEI (ULTEM 9085)HIGHTEMPTPU 85AFLEX
Market snapshot
Listing priceUSD/kg; dated snapshots$309.80/kg median; $220.00–$392.00/kg across 6 dated product listings$89.89/kg median; $31.99–$106.05/kg across 6 dated product listings
Identity & Market
Base polymer / chemistryPolyetherimide, ULTEM 9085 grade — the flame-retardant PEI used for aircraft interiors[1]Soft thermoplastic polyurethane at 82–85 Shore A[2][3][4]
Densityg/cm³1.34 (ISO 1183, 3DXTech) against 1.27 specific gravity on moulded plaques (ASTM D792, Stratasys) — the two suppliers disagree[1][5]1.11 (BASF Ultrafuse 85A) to 1.19 (NinjaFlex 85A), ISO 1183 / ASTM D792[4][2]
Typical priceUSD/kg1 kg-equivalent spools cluster near 298[6][7][8][9]1 kg-equivalent spools span 32–106; the middle of the market is about 90[6][10][2]
Price range across brandsUSD/kg220-392 across brands and formats; 3DXTech ThermaX PEI 9085 220 at 2 kg, 3D4Makers 270 at 2 kg, Fiberlogy 298 at 500 g, Kimya 321 at 500 g, IEMAI 3D 385 at 1 kg, 3DXTech CarbonX PEI 9085+CF 392[6][7][8][9][11]32–106 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[12][6][10][13][2]
Market availability1–5Niche, a handful of specialist brands[6][7][8][9]Available from several mainstream brands[6][12]
Spool sizes & diameters1.75 and 2.85 mm; 250 g to 2 kg spools, plus Stratasys canisters[6][9][5]1.75, 2.85 and 3 mm; 0.5, 1 and 2 kg spools[6][12][2]
Typical applicationsAircraft interior parts and rail rolling stock, where the flame, smoke and toxicity rating is the requirement[1]Soft-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°C130–140 (3DXTech)[1]40 (BASF Ultrafuse 85A)[4]
Enclosure / chamber requirement1–5Actively heated chamber required[14][15]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[16][17]
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 tendency1–5Severe — heated chamber needed[14]None[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[18][17]
Overall printing difficulty1–5Expert / industrial hardware only[14][15]Advanced — 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 required1–4Brass fine indefinitely for unfilled grades, but brass softens near these nozzle temperatures — hardened or plated hot ends are the norm[14]Brass fine indefinitely[19]
Abrasiveness1–5Non-abrasive when unfilled[1]Non-abrasive[19]
Nozzle clog risk1–5Moderate — needs dry filament and a clean nozzle; 3DXTech lists no special nozzle concerns but a mandatory 120 °C pre-dry before every print[20]High — jams from moisture, heat creep or particles[18][17]
Heat-creep / jam sensitivity1–5Not documentedVery high — softens in the cold zone readily; soft filament buckles between the drive gear and the melt zone[17][2]
Hotend requirementNot documentedNo special hot-end required, but a direct-drive extruder is (Simplify3D)[16]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Not documentedModerate — 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[18]
Effect of moisture on strengthNo dry-versus-conditioned figures are published; 3DXTech mandates a 120 °C, 4 h pre-dry before every print because trapped water flashes to steam at these nozzle temperatures[20]Polymaker groups TPU with the highly hygroscopic materials; wet TPU prints with poor layer adhesion and weak, brittle layers[18]
Storage requirementNot documentedSealed with desiccant; often kept in a dryer during the print[18]
Mechanical Properties
Tensile strength (XY)MPa63-77 at break (printed XZ, ASTM D638, Stratasys F900/F3300/Fortus 450mc, three tips and two colours); 54 (printed XY, ISO 527, 3DXTech)[5][1]26 ultimate (NinjaFlex 85A, ASTM D638)[2]
Young's modulusMPa2040-2540 (printed XZ, ASTM D638, Stratasys); 2050 (printed XY, ISO 527, 3DXTech)[5][1]12 (NinjaFlex 85A, ASTM D638) — two orders of magnitude below any rigid filament; NinjaTek's 95A Cheetah reaches 26 by the same method[2][21]
Elongation at break%5.4-9.1 at break (printed XZ, ASTM D638, Stratasys); 1.9-4.3 in ZX; 3DXTech quotes 3 (ISO 527)[5][1]650 at break (Filaflex 82A) and 660 (NinjaFlex 85A); BASF measures 600 in XY and 320 in ZX[3][2][4]
Flexural strengthMPa104-116 at break (printed XZ, ASTM D790 Procedure A, Stratasys); 72-98 in ZX; 3DXTech quotes 90 (ISO 178)[5][1]Not documented
Flexural modulusMPa2400-2550 (printed XZ, ASTM D790, Stratasys F900 T16 and T16A) against 2120-2130 in ZX; 3DXTech quotes 2170 (ISO 178)[5][1]Not documented
Other impact dataIzod notched 88.5-140 J/m XZ against 37-80 J/m ZX; unnotched 647-2260 J/m XZ against 169-633 J/m ZX (printed, ASTM D256/D4812, Stratasys, across three printers and three tips)[5]Not documented
Layer adhesion / Z tensileMPa39-63 at break (printed ZX, ASTM D638, Stratasys); the low end is the F900 T16 baseline, the high end the F3300 N500 hot end[5]Not documented
Brittleness1–5Brittle — snaps with little warning[1]Very ductile — bends far before failing[2]
Hardness (scale-specific)Shore A / Shore D / RockwellRockwell M110 / R126 on extruded PEI stock (ASTM D785)[22]29 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 load1–5Excellent — holds load for years. Printed ZX coupons keep 87 % of room-temperature tensile strength at 104 °C and 70 % at 132 °C (ASTM D638); extruded PEI stock is rated 170 °C long-term service[5][22]Poor — 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[23]
Fatigue / repeated-flex resistance1–5Not documentedExcellent — living hinges viable[17]
Elasticity / flexibility1–5Rigid[1]Rubbery / highly elastic[2][3]
Z strength as % of XY%56-86 (Stratasys ZX against XZ tensile at break, ASTM D638, across F900/F3300/Fortus 450mc and T16/T20/T40A tips); 58 on the F900 T16 baseline[5]53 — 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
HDT at 0.45 MPa°C158 (printed XY, ISO 75 at 0.45 MPa, 3DXTech) to 178 (printed XY 178.2 and ZX 178.4, ASTM D648 Method B at 66 psi, Stratasys); moulded 176.9[1][5]Not documented
HDT at 1.8 MPa°C170-173 (printed XY 170.2 and ZX 172.6, ASTM D648 Method B at 264 psi); moulded 172.9[5]Not documented
Glass transition (Tg)°C177 (moulded plaque, ASTM D7426 inflection point, Stratasys); 186 (DSC, 3DXTech)[5][1][24]Not documented
Melting point / Vicat°CNot documented216 melting (NinjaFlex 85A, DSC)[2]
Continuous service temperature°C170 long-term service on extruded PEI stock, converted from 338 °F; 200 short term[22]Not documented
Thermal expansion (CTE)µm/m·K44.9 (printed XY, -50 to 80 °C, ASTM E831), falling to 31.4 over 80-160 °C; ZX gives 44.5 over -50 to 60 °C. Black pigment raises it to 51.9[5]Not documented
Flammability / UL 94UL 94 V-0 at 1.5 mm on the base resin. Printed parts are tested to 14 CFR 25.853, BSS 7238 and 7239 and AITM 2.0007B and 3.0005 covering 60 s and 12 s vertical burn, 15 s horizontal burn, smoke density, toxic gas emission and OSU heat release[1][5]Not documented
Environment & Chemical
UV resistance1–5Good — years with some colour shift. 1000 h of QUV cycling to ASTM G154 left printed ZX coupons at 55.5 MPa yield against 56.0 unexposed, with elongation and modulus unchanged[5]Good — years with some colour shift; Polymaker lists UV exposure among the conditions TPU withstands[17]
Chemical resistanceNot documentedWithstands industrial solvents and UV exposure (Polymaker)[17]
Food contactNot documentedNot food safe without specific certification (Polymaker)[17]
Biodegradability / compostabilityNot documentedNot biodegradable[17]
RecyclabilityNot documentedNot accepted in household plastic collection[17]
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised. None of these polymers was in the chamber study, and all are processed far above the temperatures it covered[25]Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[25]
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[25]Open a window / occasional ventilation[25]
Post-Processing
Sanding & machiningNot documentedDifficult to sand or smooth; Polymaker limits post-processing to trimming or tumbling[17]
Gluing & solvent weldingNot documentedCyanoacrylate bonds TPU; no common solvent welds it[17]
Vapour / chemical smoothingNot documentedNo practical vapour smoothing[17]
Support material pairingNot documentedPolymaker warns TPU supports are often very difficult to remove[17]
Solvents & Solubility
Soluble inChlorinated hydrocarbons — dichloromethane and chloroform — are solvents for polyetherimide. Laboratory reagents.[26][27]DMF, DMSO, NMP and THF dissolve TPU; acetone, MEK and cyclohexanone are partial solvents. All laboratory reagents.[28]
Softened or crazed byAcetone, MEK, benzene, toluene and butyl acetate craze or stress-crack it; alcohols, fuels and dilute acids do not.[27][26]Toluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[28]
Solvent welding & smoothing agentDichloromethane is the only welding route, and it is a controlled carcinogen rather than a workshop material.[26][27]None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[28]

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. ThermaX PEI 9085 Technical Data Sheet v4 3DXTech · 2026-08 · tds
  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. ULTEM 9085 Resin — FDM Material Data Sheet Stratasys · 2026-04 · tds
  6. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  7. Kimya PEI-9085 Natural 2.85 mm 500 g igo3d · 2026-08 · vendor
  8. Fiberlogy PEI 9085 Natural, 1.75 mm / 500 g 3DJAKE · 2026-08 · vendor
  9. 3D4Makers product catalogue 3D4Makers · 2026-08 · vendor
  10. Siraya Tech Flex TPU 85A Filament — product page Siraya Tech · 2026-08 · vendor
  11. IEMAI 3D PEI 9085 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  12. Proto-pasta product catalogue Proto-pasta · 2026-08 · vendor
  13. add:north TPU Pro Matte 85A product page add:north · 2026-08 · vendor
  14. Prusament PEI 1010 Technical Datasheet v1.0 Prusa Polymers · 2024-09 · tds
  15. Prusament PEI 1010 — material page Prusa Polymers · 2026-08 · doc
  16. Flexible (TPE/TPU) — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  17. TPU — material basics Polymaker Wiki · 2026-08 · doc
  18. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  19. Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
  20. THERMAX PEI 9085 — product page (print recommendations) 3DXTech · 2026-08 · doc
  21. NinjaTek technical specs comparison chart (Cheetah, NinjaFlex, Armadillo, Alloy 910, Nylon 645) NinjaTek · 2026-08 · tds
  22. TECAPEI natural (PEI) — stock shape properties Ensinger · 2026-08 · tds
  23. BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · test
  24. ThermaX PEI 1010 Technical Data Sheet v4 3DXTech · 2026-08 · tds
  25. 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
  26. Radel PPSU, Veradel PESU, Acudel modified PPSU Design Guide — environmental stress cracking tables Solvay Specialty Polymers · 2026-08 · tds
  27. Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds
  28. Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds