3D Printing Info

Filament comparison

PEI 9085 vs PSU

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

PEI (ULTEM 9085) guidePSU guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PEI 9085 comparisonsMore PSU comparisons
PEI 9085 vs PSU — documented properties and sources
PropertyPEI (ULTEM 9085)HIGHTEMPPSUHIGHTEMP
Market snapshot
Listing priceUSD/kg; dated snapshots$309.80/kg median; $220.00–$392.00/kg across 6 dated product listings$168.00/kg median; $168.00–$168.00/kg across 1 dated product listings
Identity & Market
Base polymer / chemistryPolyetherimide, ULTEM 9085 grade — the flame-retardant PEI used for aircraft interiors[1]Polysulfone — the lowest-temperature and cheapest of the sulfone family[2]
Densityg/cm³1.34 (ISO 1183, 3DXTech) against 1.27 specific gravity on moulded plaques (ASTM D792, Stratasys) — the two suppliers disagree[1][3]1.24 (ISO 1183)[2]
Typical priceUSD/kg1 kg-equivalent spools cluster near 298[4][5][6][7]1 kg-equivalent spools cluster near 250[4]
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[4][5][6][7][8]168-250 across formats; 250 g spool $42 (168/kg), 500 g $125 (250/kg) — 3DXTech is the only filament supplier found[4]
Market availability1–5Niche, a handful of specialist brands[4][5][6][7]Special order, 1–2 makers worldwide[4]
Spool sizes & diameters1.75 and 2.85 mm; 250 g to 2 kg spools, plus Stratasys canisters[4][7][3]1.75 mm; 250 g and 500 g spools[4]
Typical applicationsAircraft interior parts and rail rolling stock, where the flame, smoke and toxicity rating is the requirement[1]Transparent high-temperature housings, medical trays and hot-water fittings[2]
Printing Parameters
Bed temperature°C130–140 (3DXTech)[1]120–140 (3DXTech)[2]
Enclosure / chamber requirement1–5Actively heated chamber required[9][10]Actively heated chamber required[9][10]
Warping tendency1–5Severe — heated chamber needed[9]Not documented
Overall printing difficulty1–5Expert / industrial hardware only[9][10]Expert / industrial hardware only[9][10]
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[9]Brass fine indefinitely for unfilled grades, but brass softens near these nozzle temperatures — hardened or plated hot ends are the norm[9]
Abrasiveness1–5Non-abrasive when unfilled[1]Non-abrasive when unfilled[2]
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[11]Moderate — needs dry filament and a clean nozzle; 3DXTech lists no special nozzle concerns but a mandatory 120 °C pre-dry before every print[12]
Moisture Behaviour
Equilibrium moisture content at ~50 % RH%Not documented0.30 in 24 h on extruded stock (ASTM D570)[13]
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[11]No 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[12]
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)[3][1]52 (printed XY, ISO 527, 3DXTech); 81 at break on extruded stock (ASTM D638)[2][13]
Young's modulusMPa2040-2540 (printed XZ, ASTM D638, Stratasys); 2050 (printed XY, ISO 527, 3DXTech)[3][1]2100 (printed XY, ISO 527)[2]
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)[3][1]8 (printed XY, ISO 527) against 50 on extruded stock — nearly three times PPSU's printed 3 %[2][14][13]
Flexural strengthMPa104-116 at break (printed XZ, ASTM D790 Procedure A, Stratasys); 72-98 in ZX; 3DXTech quotes 90 (ISO 178)[3][1]87 (printed XY, ISO 178)[2]
Flexural modulusMPa2400-2550 (printed XZ, ASTM D790, Stratasys F900 T16 and T16A) against 2120-2130 in ZX; 3DXTech quotes 2170 (ISO 178)[3][1]2050 (printed XY, ISO 178)[2]
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)[3]Izod notched 69 J/m on extruded PSU stock, converted from 1.3 ft-lb/in (ASTM D256)[13]
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[3]Not documented
Brittleness1–5Brittle — snaps with little warning[1]Moderate[2]
Hardness (scale-specific)Shore A / Shore D / RockwellRockwell M110 / R126 on extruded PEI stock (ASTM D785)[15]Rockwell M120 on extruded PSU stock (ASTM D785)[13]
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[3][15]Good. Ensinger lists high creep resistance as a headline property of extruded PSU stock, which is rated to 173 °C heat deflection at 1.8 MPa[13]
Elasticity / flexibility1–5Rigid[1]Rigid[2]
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[3]Not documented
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][3]172 (printed XY, ISO 75 at 0.45 MPa, 3DXTech); 181 on extruded stock, converted from 358 °F at 66 psi[2][13]
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[3]174 on extruded PSU stock, converted from 345 °F at 264 psi (ASTM D648)[13]
Glass transition (Tg)°C177 (moulded plaque, ASTM D7426 inflection point, Stratasys); 186 (DSC, 3DXTech)[3][1][16]187 (DSC, 3DXTech) and 185 on extruded stock (ASTM D3418), against 230 for PPSU[2][14][13]
Continuous service temperature°C170 long-term service on extruded PEI stock, converted from 338 °F; 200 short term[15]141 long-term service on extruded PSU stock, converted from 285 °F[13]
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[3]55.8 (extruded PSU stock, ASTM D696; source states 3.1e-5 in/in/°F)[13]
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][3]UL 94 V-0 on extruded PSU stock[13]
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[3]Not documented
Electrical & ESD propertiesNot documentedSurface resistance above 10¹³ ohm/sq — an insulator (IEC 60093)[2]
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[17]Moderate — 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[17]
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[17]Ventilated room or enclosure recommended[17]
Solvents & Solubility
Soluble inChlorinated hydrocarbons — dichloromethane and chloroform — are solvents for polyetherimide. Laboratory reagents.[18][19]Chlorinated hydrocarbons — dichloromethane, chloroform — dissolve polysulfone; ketones and esters attack it as well.[18][19]
Softened or crazed byAcetone, MEK, benzene, toluene and butyl acetate craze or stress-crack it; alcohols, fuels and dilute acids do not.[19][18]Acetone, MEK, ethyl acetate, benzene and toluene craze or stress-crack it; methanol and isopropanol only marginally.[19][18]
Solvent welding & smoothing agentDichloromethane is the only welding route, and it is a controlled carcinogen rather than a workshop material.[18][19]Dichloromethane cement welds PSU and NMP softens residual resin. Both are laboratory reagents.[18]

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. ThermaX PSU Technical Data Sheet v3 3DXTech · 2026-08 · tds
  3. ULTEM 9085 Resin — FDM Material Data Sheet Stratasys · 2026-04 · tds
  4. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  5. Kimya PEI-9085 Natural 2.85 mm 500 g igo3d · 2026-08 · vendor
  6. Fiberlogy PEI 9085 Natural, 1.75 mm / 500 g 3DJAKE · 2026-08 · vendor
  7. 3D4Makers product catalogue 3D4Makers · 2026-08 · vendor
  8. IEMAI 3D PEI 9085 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  9. Prusament PEI 1010 Technical Datasheet v1.0 Prusa Polymers · 2024-09 · tds
  10. Prusament PEI 1010 — material page Prusa Polymers · 2026-08 · doc
  11. THERMAX PEI 9085 — product page (print recommendations) 3DXTech · 2026-08 · doc
  12. THERMAX PSU — product page (print recommendations) 3DXTech · 2026-08 · doc
  13. TECASON S natural (PSU) — stock shape properties Ensinger · 2026-08 · tds
  14. ThermaX PPSU Technical Data Sheet v3 3DXTech · 2026-08 · tds
  15. TECAPEI natural (PEI) — stock shape properties Ensinger · 2026-08 · tds
  16. ThermaX PEI 1010 Technical Data Sheet v4 3DXTech · 2026-08 · tds
  17. 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
  18. Radel PPSU, Veradel PESU, Acudel modified PPSU Design Guide — environmental stress cracking tables Solvay Specialty Polymers · 2026-08 · tds
  19. Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds