3D Printing Info

Filament comparison

Conductive vs e-TPU

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

Conductive filament guideFoaming / expanded TPU (TPU Aero / TPU Air) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore Conductive comparisonsMore e-TPU comparisons
Conductive vs e-TPU — documented properties and sources
PropertyConductive filamentSPECIALTYFoaming / expanded TPU (TPU Aero / TPU Air)FLEX
Market snapshot
Listing priceUSD/kg; dated snapshots$170.36/kg median; $89.99–$796.00/kg across 4 dated product listings$52.05/kg median; $41.99–$85.29/kg across 6 dated product listings
Identity & Market
Base polymer / chemistryA carbon-filled compound conductive by volume rather than merely dissipative; Proto-pasta's is PLA-based, Recreus's and NinjaTek's are TPU, and add:north's Koltron G1 does not state its base polymer[1][2][3][4]Foaming thermoplastic polyurethane — a blowing agent expands the extrudate so the printed Shore hardness can be tuned by flow rate[5]
Densityg/cm³Not documented1.15 filament (Siraya Tech Flex TPU Air) and 1.05 (Roamr TPU Air HR), ISO 1183; the printed part falls to 0.51–0.93 depending on nozzle temperature (ISO 845)[6][7]
Typical priceUSD/kg1 kg-equivalent spools span 90–181 for the carbon-filled grades; add:north's Koltron G1 sits far above at 796 because it is sold only in 100 and 250 g coils[8][9][10]1 kg-equivalent spools span 42–85; the middle of the market is about 52[2][11][12][13][14][15]
Price range across brandsUSD/kg90–796 across brands; Proto-pasta conductive PLA 90 at 1 kg, Recreus Conductive Filaflex 160 at 500 g, NinjaTek Eel 181 at 1 kg, add:north Koltron G1 796 at 250 g[8][2][9][10]42–85 across brands; QIDI TPU-Aero 42, Siraya Tech Flex TPU Air 45, Phaetus aeFlex TPU-Aero 49 direct and 40 at West3D, Roamr TPU Air HR 80A 55 at 800 g, Recreus Filaflex Foamy 73 at 750 g, colorFabb varioShore 85 at 700 g[2][11][12][13][14][15][16]
Market availability1–5Niche, a handful of specialist brands[8][2]Available from several mainstream brands — colorFabb, Recreus, QIDI, Phaetus, Siraya Tech and FusRock all sell an active-foaming TPU[5][2][11][12][14][15]
Spool sizes & diameters1.75 and 2.85 mm; 0.05, 0.1, 0.25, 0.5, 1 and 2 kg spools[8][2][9][10]1.75 mm; 0.7, 0.75, 0.8, 1 and 3 kg spools[5][2][12][13][15]
Typical applicationsCapacitive touch surfaces, low-current traces, EMI shielding and static-safe fixtures[1]Cushioning, midsoles, insoles and soft-touch parts where the softness needs to vary within one print; Siraya Tech's Roamr line is aimed specifically at printed footwear[5][13]
Diameter tolerance± mmNot documented0.03 (Siraya Tech and Roamr, 1.75 mm)[6][7]
Printing Parameters
Nozzle temperature°CNot documented230–270 (QIDI and Siraya Tech), 220–260 (Roamr); foaming activates near 230 °C and is strongest at the top of the range[5][6][7][14]
Bed temperature°CNot documented30–45 (QIDI and Siraya Tech), 35–50 (Roamr) — a hot bed makes the foamed part over-stick[6][7][14]
Enclosure / chamber requirement1–5Open frame is fine[1]Open frame is fine — Roamr states no enclosure is required[5][7]
Part cooling fanNot documented100 % — cooling sets the foamed structure quickly (Siraya Tech and Roamr)[6][7]
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, and Siraya Tech recommends PVP glue or Magigoo as a release agent on PEI[17][18][6]
Maximum volumetric flow (mm³/s; see test conditions)mm³/sNot documentedUp to 12 (Siraya Tech, Flex TPU Air)[12]
Stringing / oozing tendency1–5Not documentedSevere — the material expands inside the hot end, so it oozes on travel moves; QIDI states retraction tuning cannot fix it and Siraya Tech advises setting retraction distance and speed to zero[6][14]
Overall printing difficulty1–5Intermediate — dry filament and a tuned profile[1]Advanced — enclosure, hardware upgrades, tuning; both density and hardness follow nozzle temperature and flow[5]
Extruder requirementNot documentedDirect drive; the base material is a 92A TPU[5][19]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass acceptable; hardened steel for volume work[1]Brass fine indefinitely — Roamr states plainly that no hardened nozzle is needed[20][7]
Abrasiveness1–5Moderately abrasive — conductive carbon filler[1]Non-abrasive[20]
Nozzle clog risk1–5Low — Proto-pasta states the carbon-filled grade prints on standard PLA settings with no special nozzle required[1]Not documented
Hotend requirementNot documentedNo special hot-end required, but a direct-drive extruder is (Simplify3D)[17]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Not documentedModerate[21]
Equilibrium moisture content at ~50 % RH%Not documented1.09 water absorption (QIDI TPU-Aero; the standard is not stated)[14]
Drying temperature & timeNot documented70–80 °C for 4–6 h; keep below 15 % RH while printing (Siraya Tech, Roamr and QIDI)[6][7][14]
Symptoms when wetNot documentedBubbling and popping at the nozzle, stringing and a rough surface; Siraya Tech adds that moisture wrecks the foaming itself, not only the surface[21][6]
Effect of moisture on strengthPolymaker rates PLA low-sensitivity and publishes no dry-versus-conditioned figures; absorbed water flashes to steam and shows as bubbling and poor layer adhesion[21]Polymaker groups TPU with the highly hygroscopic materials; no dry-versus-conditioned figures are published[21]
Storage requirementNot documentedSealed with desiccant; often kept in a dryer during the print[21]
Mechanical Properties
Tensile strength (XY)MPaNot documentedFalls with foaming: colorFabb 24 unfoamed and 12 foamed (ISO 527-1A); Siraya Tech 10.3 at break printed at 240 °C down to 3.8 at 270 °C; QIDI 6.81 at break (ISO 527, XY)[5][6][14]
Young's modulusMPaNot documented50 unfoamed and 40 foamed (colorFabb, ISO 527-1A)[5]
Elongation at break%Not documented465 unfoamed and 450 foamed (colorFabb, ISO 527-1A); Siraya Tech 629 at 240 °C down to 475 at 270 °C; Roamr 760 down to 540; QIDI 576 (ISO 527, XY)[5][6][7][14]
Flexural modulusMPaNot documented50 unfoamed and 40 foamed flexural modulus (colorFabb, ISO 178)[5]
Brittleness1–5Brittle — snaps with little warning; carbon-black loading at conductive levels embrittles PLA[1]Very ductile — bends far before failing[5]
Hardness (scale-specific)Shore A / Shore D / RockwellNot documentedTunable by nozzle temperature: colorFabb 92 Shore A unfoamed; Siraya Tech 78 A printed at 240 °C falling to 63 A at 270 °C, Roamr TPU Air HR 80A 80 A down to 66 A and HR 85A 83 A down to 70 A (ISO 7619)[5][6][7][22]
Creep resistance / sustained load1–5Not documentedPoor — no foamed-grade creep test; a printed 95A TPU bar crept from 74.5 to 82.7 mm over 5 days at 1.25 kg[23]
Fatigue / repeated-flex resistance1–5Not documentedExcellent — living hinges viable[18]
Elasticity / flexibility1–5Rigid[1]Rubbery / highly elastic[5]
Thermal Properties
Melting point / Vicat°CNot documentedVicat softening drops as the foam expands: 83 printed at 240 °C to 53 at 270 °C (Siraya Tech, ISO 306); QIDI 70.4[6][14]
Annealing responseNot documentedFoaming activates near 230 °C and expands the extrudate about 1.6×; colorFabb advises dropping flow to 60–70 % to realise the weight saving, and Siraya Tech publishes a flow schedule from 85–90 % at 230 °C down to 50–55 % at 270 °C[5][6]
Environment & Chemical
UV resistance1–5Not documentedGood — years with some colour shift; Polymaker lists UV exposure among the conditions TPU withstands[18]
Chemical resistanceNot documentedWithstands industrial solvents and UV exposure (Polymaker)[18]
Food contactNot documentedNot food safe without specific certification (Polymaker)[18]
Biodegradability / compostabilityNot documentedNot biodegradable[18]
RecyclabilityNot documentedNot accepted in household plastic collection[18]
Electrical & ESD propertiesConductive rather than dissipative — Proto-pasta sells the grade as electrically conductive composite PLA[1]Not documented
Health & Safety
Fume toxicity1–5Low hazard — minimal VOC and particle emission; none of these materials was in the chamber study[24]Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[24]
Ventilation / filtration requirement1–5Open a window / occasional ventilation[24]Open a window / occasional ventilation[24]
Dust & fibre handling hazardConductive carbon filler is bound in the matrix; avoid inhaling sanding dust[1]Not documented
Post-Processing
Sanding & machiningNot documentedDifficult to sand or smooth; Polymaker limits post-processing to trimming or tumbling[18]
Gluing & solvent weldingNot documentedCyanoacrylate bonds TPU; no common solvent welds it[18]
Vapour / chemical smoothingNot documentedNo practical vapour smoothing[18]
Support material pairingNot documentedPolymaker warns TPU supports are often very difficult to remove[18]
Dimensional accuracy & detailNot documentedFoamed surfaces are matte and textured; holding a consistent hardness means holding the nozzle temperature steady, and the printed density moves by nearly a factor of two across the 230–270 °C window[5][6]
Solvents & Solubility
Soluble inChloroform dissolves PLA-based grades, leaving the carbon black; TPU-based grades need DMF, NMP or THF. Laboratory reagents.[25][26]DMF, DMSO, NMP and THF dissolve TPU; acetone, MEK and cyclohexanone are partial solvents. All laboratory reagents.[26]
Softened or crazed byAcetone and ethyl acetate plasticise a PLA-based grade; a TPU-based grade swells in toluene, esters and alcohols.[25][26]Toluene and benzene swell it up to +50 % by weight at 23 °C; the foamed wall soaks up esters and alcohols faster still.[26]
Solvent welding & smoothing agentNone — neither PLA nor TPU has a workshop-safe welding or smoothing solvent.[25][26]None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[26]

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. Electrically Conductive Composite PLA — product page and technical data Proto-pasta · 2026-08 · tds
  2. Recreus product catalogue Recreus · 2026-08 · vendor
  3. Eel 3D Printing Filament Technical Specifications NinjaTek · 2026-08 · tds
  4. Koltron G1 Technical Data Sheet add:north · 2026-08 · tds
  5. varioShore TPU Technical Data Sheet colorFabb · 2026-08 · tds
  6. Siraya Tech Flex TPU Air Technical Data Sheet Siraya Tech · 2026-08 · tds
  7. Roamr TPU Air HR 80A Technical Data Sheet Siraya Tech · 2026-08 · tds
  8. Proto-pasta product catalogue Proto-pasta · 2026-08 · vendor
  9. Eel product page — durometer, print guidelines and price NinjaTek · 2026-08 · vendor
  10. add:north Koltron G1 product page add:north · 2026-08 · vendor
  11. varioShore TPU Natural — product page colorFabb US · 2026-08 · vendor
  12. Siraya Tech Flex TPU Air Black Filament — lightweight foaming flexible, product page Siraya Tech · 2026-08 · vendor
  13. Roamr TPU Air HR 80A Filament — product page Siraya Tech · 2026-08 · vendor
  14. TPU-Aero Lightweight TPU Filament — product page with specification tables QIDI Tech · 2026-08 · vendor
  15. aeFlex TPU-Aero — active foaming low weight TPU, product page Phaetus · 2026-08 · vendor
  16. Phaetus aeWorthy TPU-Aero — reseller listing West3D · 2026-08 · vendor
  17. Flexible (TPE/TPU) — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  18. TPU — material basics Polymaker Wiki · 2026-08 · doc
  19. NinjaFlex 85A Technical Specifications NinjaTek · 2026-08 · tds
  20. Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
  21. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  22. Roamr TPU Air HR 85A Technical Data Sheet Siraya Tech · 2026-08 · tds
  23. BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · test
  24. 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
  25. Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
  26. Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds