3D Printing Info

Filament comparison

Conductive vs TPU-CF

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

2 selected · all documented properties

Conductive vs TPU-CF — documented properties and sources
PropertyConductive filamentSPECIALTYCarbon-fibre TPUFLEX
Market snapshot
Listing priceUSD/kg; dated snapshots$170.36/kg median; $89.99–$796.00/kg across 4 dated product listings$107.05/kg median; $107.05–$107.05/kg across 1 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]Carbon-fibre reinforced thermoplastic polyurethane at the hard end of the range[5]
Densityg/cm³Not documented1.22 (Extrudr FLEX HARD CF, ISO 2781)[5]
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[6][7][8]107 for the only retail listing found (Extrudr 0.5 kg coil, incl. VAT)[9]
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[6][2][7][8]One listing only: EUR 49.56 incl. VAT per 0.5 kg coil, direct from Extrudr; no reseller or second brand found[9]
Market availability1–5Niche, a handful of specialist brands[6][2]Niche, a handful of specialist brands — Extrudr's FLEX HARD CF is the only carbon-filled flexible with a published datasheet found here[5]
Spool sizes & diameters1.75 and 2.85 mm; 0.05, 0.1, 0.25, 0.5, 1 and 2 kg spools[6][2][7][8]1.75 mm; 0.5 and 2 kg coils[9]
Typical applicationsCapacitive touch surfaces, low-current traces, EMI shielding and static-safe fixtures[1]Stiffened flexible parts — damping mounts and semi-rigid brackets[5]
Printing Parameters
Nozzle temperature°CNot documented230–260 (Extrudr FLEX HARD CF)[5]
Bed temperature°CNot documented50–90 (Extrudr FLEX HARD CF)[5]
Enclosure / chamber requirement1–5Open frame is fine[1]Open frame is fine[5]
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 documented1.6–8 at the 20–100 mm/s Extrudr specifies on a 0.4 mm nozzle at 0.2 mm layer[5]
Overall printing difficulty1–5Intermediate — dry filament and a tuned profile[1]Advanced — enclosure, hardware upgrades, tuning; hardened nozzle needed[5]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass acceptable; hardened steel for volume work[1]Hardened steel required — Extrudr marks FLEX HARD CF as needing a hardened nozzle where its unfilled FLEX grades do not[5]
Abrasiveness1–5Moderately abrasive — conductive carbon filler[1]Highly abrasive — standard CF composite[5]
Nozzle clog risk1–5Low — Proto-pasta states the carbon-filled grade prints on standard PLA settings with no special nozzle required[1]High — jams from moisture, heat creep or particles; a flexible base plus chopped carbon fibre, which Prusa lists as a higher nozzle-clogging risk, and Extrudr requires a hardened nozzle[12][5][10]
Hotend requirementNot documentedNo special hot-end required, but a direct-drive extruder is (Simplify3D)[10]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Not documentedModerate[13]
Drying temperature & timeNot documented60 °C for 6 h (Extrudr FLEX HARD CF)[5]
Symptoms when wetNot documentedBubbling and popping at the nozzle, stringing and a rough surface[13]
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[13]Polymaker groups TPU with the highly hygroscopic materials; no dry-versus-conditioned figures are published[13]
Storage requirementNot documentedSealed with desiccant; often kept in a dryer during the print[13]
Mechanical Properties
Young's modulusMPaNot documented35 (Extrudr FLEX HARD CF, ISO 527-2/5A/500)[5]
Elongation at break%Not documented380 ultimate elongation (Extrudr FLEX HARD CF, ISO 527-2/5A/500), against 490 for the unfilled FLEX HARD[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 documented70 Shore D (Extrudr FLEX HARD CF, ISO 868), against 58 Shore D for the unfilled FLEX HARD[5]
Creep resistance / sustained load1–5Not documentedBelow average — no CF-grade creep test; the grade is 70 Shore D where a 95A TPU bar crept from 74.5 to 82.7 mm over 5 days at 1.25 kg[5][14]
Fatigue / repeated-flex resistance1–5Not documentedGood — 380 % ultimate elongation and a damping application set (Extrudr cites longboard wheels), below the unfilled grades[5]
Elasticity / flexibility1–5Rigid[1]Semi-flexible[5]
Wear resistance & frictionNot documentedAbrasion 26 mm³ (Extrudr FLEX HARD CF, ISO 4649-A) — the same as the unfilled FLEX HARD[5]
Thermal Properties
Glass transition (Tg)°CNot documented-24 (Extrudr FLEX HARD CF)[5]
Melting point / Vicat°CNot documentedVicat A 140 (Extrudr FLEX HARD CF, ISO 306)[5]
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]
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[15]Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[15]
Ventilation / filtration requirement1–5Open a window / occasional ventilation[15]Open a window / occasional ventilation[15]
Dust & fibre handling hazardConductive carbon filler is bound in the matrix; avoid inhaling sanding dust[1]Carbon fibre is bound in the matrix; sanding dust should not be inhaled[5]
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]
Dimensional accuracy & detailNot documentedTear strength 165 kN/m (Extrudr FLEX HARD CF, ISO 34-1B)[5]
Solvents & Solubility
Soluble inChloroform dissolves PLA-based grades, leaving the carbon black; TPU-based grades need DMF, NMP or THF. Laboratory reagents.[16][17]DMF, DMSO, NMP and THF dissolve the TPU matrix and leave the fibre; ketones are partial solvents. Laboratory reagents.[17]
Softened or crazed byAcetone and ethyl acetate plasticise a PLA-based grade; a TPU-based grade swells in toluene, esters and alcohols.[16][17]Toluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[17]
Solvent welding & smoothing agentNone — neither PLA nor TPU has a workshop-safe welding or smoothing solvent.[16][17]None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[17]

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. Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
  6. Proto-pasta product catalogue Proto-pasta · 2026-08 · vendor
  7. Eel product page — durometer, print guidelines and price NinjaTek · 2026-08 · vendor
  8. add:north Koltron G1 product page add:north · 2026-08 · vendor
  9. Extrudr TPU FLEX Hard CF — product page (1.75 mm, 0.5 and 2 kg coils, price) Extrudr (FD3D GmbH) · 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. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  13. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  14. BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · test
  15. 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
  16. Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
  17. Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds