3D Printing Info

Filament comparison

PEI 9085 vs PP-CF

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

PEI (ULTEM 9085) guideCarbon-fibre PP (PP-CF) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PEI 9085 comparisonsMore PP-CF comparisons
PEI 9085 vs PP-CF — documented properties and sources
PropertyPEI (ULTEM 9085)HIGHTEMPCarbon-fibre PP (PP-CF)POLYOLEFIN
Market snapshot
Listing priceUSD/kg; dated snapshots$309.80/kg median; $220.00–$392.00/kg across 6 dated product listings$107.68/kg median; $57.13–$120.00/kg across 3 dated product listings
Identity & Market
Base polymer / chemistryPolyetherimide, ULTEM 9085 grade — the flame-retardant PEI used for aircraft interiors[1]Polypropylene reinforced with chopped carbon fibre[2][3]
Densityg/cm³1.34 (ISO 1183, 3DXTech) against 1.27 specific gravity on moulded plaques (ASTM D792, Stratasys) — the two suppliers disagree[1][4]0.91 (Prusament PP Carbon Fiber, ISO 1183)[2]
Typical priceUSD/kg1 kg-equivalent spools cluster near 298[5][6][7][8]1 kg-equivalent spools span 57–138; the middle of the market is about 108[9][5][10]
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[5][6][7][8][11]57–138 across brands; Reli3D 57 at 700 g on Amazon, Prusament 108 direct from Prusa and 138 at Printed Solid, 3DXTech CarbonX PP+CF 120[9][12][5][10]
Market availability1–5Niche, a handful of specialist brands[5][6][7][8]Available from several mainstream brands[5][12]
Spool sizes & diameters1.75 and 2.85 mm; 250 g to 2 kg spools, plus Stratasys canisters[5][8][4]1.75 mm; 0.65 kg spools[12][5]
Typical applicationsAircraft interior parts and rail rolling stock, where the flame, smoke and toxicity rating is the requirement[1]Lightweight chemical-resistant parts, automotive clips and ducting that must survive above 150 °C[13]
Diameter tolerance± mmNot documented±0.04 (Prusament)[2]
Printing Parameters
Nozzle temperature°CNot documented270 ± 10 (Prusament)[2]
Bed temperature°C130–140 (3DXTech)[1]85 ± 10 (Prusament)[2]
Enclosure / chamber requirement1–5Actively heated chamber required[14][15]Enclosure recommended — Simplify3D lists an enclosure as a hardware requirement and Polymaker advises one below 70 °C ambient to stop warping and cracking[16][17]
Part cooling fanNot documentedOff — Prusa runs 0 % except 100 % on bridges[2]
Maximum volumetric flow (mm³/s; see test conditions)mm³/sNot documented3.2 at Prusa's 40 mm/s cap on a 0.4 mm nozzle at 0.2 mm layer[2][18]
Warping tendency1–5Severe — heated chamber needed[14]High — enclosure needed for reliable large parts; Prusa recommends a brim[2]
Bed-adhesion difficulty1–5Not documentedVery difficult — special plates or slurry required[2]
Overall printing difficulty1–5Expert / industrial hardware only[14][15]Advanced — enclosure, hardware upgrades, tuning; hardened nozzle mandatory[2]
Extruder requirementNot documentedPrusa states a hardened nozzle is necessary and recommends a brim[2]
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]Hardened steel required — Prusa states plainly that a hardened nozzle is necessary[2]
Abrasiveness1–5Non-abrasive when unfilled[1]Highly abrasive — standard CF composite[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[19]Moderate — needs dry filament and a clean nozzle; 3DXTech specifies a hardened 0.4 mm minimum nozzle and 0.25 mm layers or higher, and Prusa lists composites as a higher clogging risk[3][20]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Not documentedNegligible (<0.1 % EMC) — Prusa measures 0.03 % in 24 h and 0.04 % in 7 days on its PP composite, the lowest figures it publishes for any filament[2]
Equilibrium moisture content at ~50 % RH%Not documented0.03 after 24 h and 0.04 after 7 days at 24 °C / 22 % RH (Prusa Polymers)[2]
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[19]Not applicable in practice at 0.04 % equilibrium uptake[2]
Storage requirementNot documentedNo special storage needed[2]
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)[4][1]21 ± 0.4 filament tensile yield (Prusament, ISO 527)[2]
Young's modulusMPa2040-2540 (printed XZ, ASTM D638, Stratasys); 2050 (printed XY, ISO 527, 3DXTech)[4][1]Not documented
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)[4][1]Not documented
Flexural strengthMPa104-116 at break (printed XZ, ASTM D790 Procedure A, Stratasys); 72-98 in ZX; 3DXTech quotes 90 (ISO 178)[4][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)[4][1]Not documented
Charpy impact, notchedkJ/m²Not documented14.5 ± 0.3 printed horizontal and 10.5 ± 0.8 printed vertical XZ (ISO 179-1, notched)[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)[4]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[4]Not documented
Brittleness1–5Brittle — snaps with little warning[1]Tough — absorbs impact, yields before breaking[2]
Hardness (scale-specific)Shore A / Shore D / RockwellRockwell M110 / R126 on extruded PEI stock (ASTM D785)[21]Rockwell R102 (and M95) on extruded unfilled PP stock (ASTM D785); no figure is published for a carbon-fibre PP filament[22]
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[4][21]Not documented
Fatigue / repeated-flex resistance1–5Not documentedGood[23]
Elasticity / flexibility1–5Rigid[1]Slightly flexible in thin sections[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[4]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][4]158 (ISO 75, 0.45 MPa) — far above unfilled PP and above most engineering filaments[2]
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[4]115 (ISO 75, 1.8 MPa)[2]
Glass transition (Tg)°C177 (moulded plaque, ASTM D7426 inflection point, Stratasys); 186 (DSC, 3DXTech)[4][1][24]Not documented
Continuous service temperature°C170 long-term service on extruded PEI stock, converted from 338 °F; 200 short term[21]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[4]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][4]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[4]Not documented
Chemical resistanceNot documentedExcellent against acids, alkalis and most solvents[17]
Water / humidity resistance in service1–5Not documentedExcellent — essentially unaffected[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[25]Low hazard — minimal VOC and particle emission. Inferred: no polyolefin was among the nine filaments in the Azimi chamber study, so this is a family-level judgement rather than a measurement[25]
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[25]Open a window / occasional ventilation. Inferred — no polyolefin was measured in the chamber study[25]
Dust & fibre handling hazardNot documentedCarbon fibre is bound in the matrix; sanding dust should not be inhaled[2]
Solvents & Solubility
Soluble inChlorinated hydrocarbons — dichloromethane and chloroform — are solvents for polyetherimide. Laboratory reagents.[26][27]None at room temperature; chloroform dissolves the matrix at 60 °C and xylene at about 118 °C, leaving the fibre.[28][29]
Softened or crazed byAcetone, MEK, benzene, toluene and butyl acetate craze or stress-crack it; alcohols, fuels and dilute acids do not.[27][26]Xylene, decalin, CCl4 and chlorobenzene are heavily absorbed at 20 °C; oleum, chlorosulphonic acid and bromine destroy 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 — nothing softens PP at room temperature, so joints have to be welded thermally rather than chemically.[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. Prusament PP Carbon Fiber Technical Datasheet v1.0 Prusa Polymers · 2024-11 · tds
  3. CarbonX PP+CF — product page 3DXTech · 2026-08 · vendor
  4. ULTEM 9085 Resin — FDM Material Data Sheet Stratasys · 2026-04 · tds
  5. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  6. Kimya PEI-9085 Natural 2.85 mm 500 g igo3d · 2026-08 · vendor
  7. Fiberlogy PEI 9085 Natural, 1.75 mm / 500 g 3DJAKE · 2026-08 · vendor
  8. 3D4Makers product catalogue 3D4Makers · 2026-08 · vendor
  9. Prusament PP Carbon Fiber Black 650g — product page Prusa Research · 2026-08 · vendor
  10. Reli3D Carbon Fiber PP Filament 1.75 mm 700 g Black — Amazon listing Amazon.com · 2026-08 · vendor
  11. IEMAI 3D PEI 9085 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  12. Printed Solid product catalogue Printed Solid · 2026-08 · vendor
  13. Prusament PP Carbon Fiber — material page Prusa Polymers · 2026-08 · doc
  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. Polypropylene — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  17. PP — material basics Polymaker Wiki · 2026-08 · doc
  18. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  19. THERMAX PEI 9085 — product page (print recommendations) 3DXTech · 2026-08 · doc
  20. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  21. TECAPEI natural (PEI) — stock shape properties Ensinger · 2026-08 · tds
  22. TECAFINE PP natural — stock shape properties Ensinger · 2026-08 · tds
  23. Centaur PP Technical Data Sheet Formfutura · 2026-08 · tds
  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. Pro-fax and Moplen polypropylene — Chemical Resistance Guide (20, 60 and 100 °C) LyondellBasell · 2026-08 · tds
  29. US 5,278,282 Polymer recycling by selective dissolution — xylene dissolution temperatures Nauman & Lynch, Rensselaer Polytechnic Institute · 1994-01 · paper