3D Printing Info

Filament comparison

PA blend vs TPU soft

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

PA6/66 copolymer blends guideSoft TPU (below 85A) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PA blend comparisonsMore TPU soft comparisons
PA blend vs TPU soft — documented properties and sources
PropertyPA6/66 copolymer blendsPASoft TPU (below 85A)FLEX
Market snapshot
Listing priceUSD/kg; dated snapshots$65.62/kg median; $62.00–$113.33/kg across 4 dated product listings$114.04/kg median; $109.80–$122.27/kg across 4 dated product listings
Identity & Market
Base polymer / chemistryPA6/66 copolymer — a nylon alloy that lowers the melting point and improves printability against straight PA6[1][2]Very soft thermoplastic elastomers below 85 Shore A. Fiberlogy's FiberFlex 30D measures 81 Shore A, the softest grade with a published datasheet found here[3]
Densityg/cm³1.12 (ISO 1183, Polymaker CoPA)[1]1.07 (Fiberlogy FiberFlex 30D, ISO 1183)[3]
Typical priceUSD/kg1 kg-equivalent spools cluster near 65[4][5][6]1 kg-equivalent spools cluster near 115[7][8][9]
Price range across brandsUSD/kg62–113 across brands; add:north Adura 62, PrimaCreator NylonPower PA6/66 65 at 500 g, Polymaker CoPA 67, 3DXTech AmideX Nylon 6-66 113[4][10][5][6]110–122 at 1 kg-equivalent; Recreus 70A 110 and 60A 116 at 500 g, NinjaTek Edge 83A 112, NinjaTek Chinchilla 75A 122; the Recreus 3 kg spools fall to 70–73[7][9][8]
Market availability1–5Available from several mainstream brands[4][10]Niche, a handful of specialist brands[3][11][7]
Spool sizes & diameters1.75 and 2.85 mm; 0.5, 0.75 and 1 kg spools[4][10][5][6]1.75, 2.85 and 3 mm; 0.5, 0.85, 1, 2 and 3 kg spools[3][7][12][8]
Typical applicationsGeneral-purpose nylon parts and, unusually, CoPA can support itself if the support is removed before it absorbs moisture[1]Highly compliant seals, soft grips and prosthetic liners[3]
Printing Parameters
Nozzle temperature°C250–270 (Polymaker CoPA)[1]Not documented
Bed temperature°C25–50 (Polymaker CoPA)[1]50–70 (Fiberlogy FiberFlex 30D)[3]
Enclosure / chamber requirement1–5Enclosure required (passive) — Polymaker specifies a chamber at ambient temperature[1]Open frame is fine[3]
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[13][14]
Maximum volumetric flow (mm³/s; see test conditions)mm³/s16 at Polymaker's 200 mm/s cap on a 0.4 mm nozzle at 0.2 mm layer[1][15]Not documented
Overall printing difficulty1–5Advanced — enclosure, hardware upgrades, tuning; must be kept below 20 % RH throughout[1][16]Expert / industrial hardware only — below 85 Shore A the filament buckles in almost any feed path that is not a short, constrained direct drive[12][14]
Extruder requirementNot documentedDirect drive only, with a constrained filament path; Bowden is not viable at this hardness[12][11]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely for unfilled grades[17]Brass fine indefinitely[18]
Abrasiveness1–5Non-abrasive when unfilled[17]Non-abrasive[18]
Nozzle clog risk1–5Very high — frequent jams without careful setup[19][16]High — jams from moisture, heat creep or particles; below 85 Shore A the filament buckles and compresses, and Simplify3D warns that raised feed rates most likely end in a jam[13][14][16]
Heat-creep / jam sensitivity1–5Not documentedVery high — softens in the cold zone readily[14]
Hotend requirementNot documentedNo special hot-end required, but a direct-drive extruder is (Simplify3D)[13]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Very high (>2 %) — Polymaker's own wet-state specimens reached 6.16 % moisture content after 48 h immersion at 60 °C[1][16]Moderate[16]
Drying temperature & time100 °C for 8 h (Polymaker CoPA)[1]Not documented
Symptoms when wetPopping and cracking during extrusion, then hard-to-diagnose defects[19]Bubbling and popping at the nozzle, stringing and a rough surface[16]
Effect of moisture on strengthMeasured dry against wet on printed specimens at 6.16 % moisture (Polymaker CoPA): tensile 78.0 → 34.3 MPa, Young's modulus 2703 → 724 MPa, flexural strength 109.8 → 22.6 MPa, while notched Charpy rises 6.9 → 27.7 kJ/m² and elongation 12.7 → 13.2 %[1][19]Polymaker groups TPU with the highly hygroscopic materials; no dry-versus-conditioned figures are published[16]
Storage requirementPolymaker states CoPA must always be stored and used below 20 % relative humidity[1]Sealed with desiccant; often kept in a dryer during the print[16]
Hydrolysis at melt temperaturePolymaker requires a 100 °C dry for 8 h and storage below 20 % RH; no molecular-weight loss figure is published, and the published wet data is conditioning rather than melt hydrolysis[1][20]Not documented
Mechanical Properties
Tensile strength (XY)MPa78.0 ± 0.7 printed XY dry and 34.3 ± 2.5 wet, ISO 527 (Polymaker CoPA)[1]Not documented
Young's modulusMPa2703 ± 259 printed XY dry and 724 ± 61 wet, ISO 527 (Polymaker CoPA)[1]Not documented
Elongation at break%12.7 ± 2.1 printed XY dry and 13.2 ± 2.3 wet, ISO 527 (Polymaker CoPA)[1]870 at break (Fiberlogy FiberFlex 30D, ISO 527) — the highest elongation in the dataset[3]
Flexural strengthMPa109.8 ± 1.3 printed XY dry and 22.6 ± 0.5 wet, ISO 178 (Polymaker CoPA)[1]Not documented
Flexural modulusMPa2510 ± 25 printed XY dry and 636 ± 11 wet, ISO 178 (Polymaker CoPA)[1]Not documented
Charpy impact, notchedkJ/m²6.9 ± 1.4 printed XY dry and 27.7 ± 1.2 wet, ISO 179 notched (Polymaker CoPA) — impact quadruples when conditioned[1]Not documented
Layer adhesion / Z tensileMPa45.8 ± 1.5 printed Z dry, falling to 13.7 ± 1.2 wet, ISO 527 (Polymaker CoPA)[1]Not documented
Brittleness1–5Tough — absorbs impact, yields before breaking[1]Very ductile — bends far before failing[3]
Hardness (scale-specific)Shore A / Shore D / RockwellShore D 86 and Rockwell 85 (108) — the source does not name the scales on extruded unfilled PA66 stock (ASTM D2240, D785)[21]81 Shore A and 30 Shore D (Fiberlogy FiberFlex 30D, ISO 7619)[3]
Creep resistance / sustained load1–5Not documentedPoor — no creep test at this hardness; a printed 95A TPU bar crept from 74.5 to 82.7 mm over 5 days at 1.25 kg[22]
Fatigue / repeated-flex resistance1–5Excellent — living hinges viable[17]Excellent — living hinges viable[14]
Elasticity / flexibility1–5Semi-flexible[19]Rubbery / highly elastic[3]
Z strength as % of XY%59 dry (45.8 Z against 78.0 XY) and 40 wet, printed[1]Not documented
Wear resistance & frictionNot documentedTear strength 95 kN/m (Fiberlogy FiberFlex 30D, ISO 34-1)[3]
Thermal Properties
HDT at 0.45 MPa°C111 (ISO 75, 0.45 MPa, Polymaker CoPA)[1]Not documented
HDT at 1.8 MPa°C70 (ISO 75, 1.8 MPa, Polymaker CoPA)[1]Not documented
Glass transition (Tg)°C66 (DSC, Polymaker CoPA)[1]Not documented
Melting point / Vicat°C189 melting (DSC); Vicat 180, crystallisation 148, decomposition 370 (Polymaker CoPA)[1]170 melting (Fiberlogy FiberFlex 30D, DSC)[3]
Annealing response80 °C for 6 h (Polymaker CoPA)[1]Not documented
Thermal expansion (CTE)µm/m·K81.0 on extruded unfilled PA66 stock (ASTM D696; source states 4.5e-5 in/in/°F) — the same chemistry as a PA6/66 copolymer[21]Not documented
Environment & Chemical
UV resistance1–5Not documentedGood — years with some colour shift; Polymaker lists UV exposure among the conditions TPU withstands[14]
Chemical resistanceNot documentedWithstands industrial solvents and UV exposure (Polymaker)[14]
Water / humidity resistance in service1–5Absorbs water, properties shift — 6.16 % uptake cost 56 % of tensile strength and 73 % of modulus[1]Not documented
Food contactNot documentedNot food safe without specific certification (Polymaker)[14]
Biodegradability / compostabilityNot documentedNot biodegradable[14]
RecyclabilityNot documentedNot accepted in household plastic collection[14]
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[23]Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[23]
VOC emission rateµg/minUp to 180 caprolactam, the dominant VOC from nylon; total VOC reached nearly 200 µg/min, the highest of the nine filaments tested[23]Not documented
Ultrafine-particle emission rateparticles/min≈2 × 10⁸ median — low for ultrafine particles despite the highest VOC mass of any filament tested[23]Not documented
Hazardous species emittedCaprolactam, at up to 180 µg/min from nylon filament — the largest single-VOC emission rate measured in the study[23]Not documented
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[23]Open a window / occasional ventilation[23]
Post-Processing
Sanding & machiningNot documentedDifficult to sand or smooth; Polymaker limits post-processing to trimming or tumbling[14]
Gluing & solvent weldingNot documentedCyanoacrylate bonds TPU; no common solvent welds it[14]
Vapour / chemical smoothingNot documentedNo practical vapour smoothing[14]
Support material pairingCoPA can support itself, but Polymaker warns the support bonds permanently if it absorbs moisture before removal[1]Polymaker warns TPU supports are often very difficult to remove[14]
Solvents & Solubility
Soluble inDissolved at 23 °C by formic acid above ~50 %, phenol, m-cresol, 96 % sulphuric acid or hexafluoroisopropanol — laboratory reagents.[24]DMF, DMSO, NMP and THF dissolve TPU; acetone, MEK and cyclohexanone are partial solvents. All laboratory reagents.[25]
Softened or crazed byZinc chloride solutions stress-crack it — 10 % marginal, 37 % not resistant; alcoholic calcium chloride dissolves it.[24]Toluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[25]
Solvent welding & smoothing agentNone — nylon's only solvents are formic acid, phenol and HFIP, all of which degrade the part they wet.[24]None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[25]

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. PolyMide CoPA Technical Data Sheet V5.4 (dry and wet status blocks) Polymaker · 2024-11 · tds
  2. AmideX Nylon 6-66 — product page 3DXTech · 2026-08 · vendor
  3. FiberFlex 30D Technical Data Sheet Fiberlogy · 2026-08 · tds
  4. Polymaker product catalogue Polymaker · 2026-08 · vendor
  5. add:north Adura product page add:north · 2026-08 · vendor
  6. PrimaCreator SELECT NylonPower PA6/66 product page PrimaCreator · 2026-08 · vendor
  7. Recreus product catalogue Recreus · 2026-08 · vendor
  8. Chinchilla product page — print guidelines, spool sizes and price NinjaTek · 2026-08 · vendor
  9. NinjaFlex Edge product page — durometer, print guidelines and price NinjaTek · 2026-08 · vendor
  10. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  11. Filaflex 82A product page (Shore hardness and elongation) Recreus · 2026-08 · vendor
  12. NinjaFlex 85A Technical Specifications NinjaTek · 2026-08 · tds
  13. Flexible (TPE/TPU) — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  14. TPU — material basics Polymaker Wiki · 2026-08 · doc
  15. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  16. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  17. PA (Nylon) — material basics Polymaker Wiki · 2026-08 · doc
  18. Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
  19. Moisture Conditioning — effect on printed nylon properties Polymaker Wiki · 2026-08 · doc
  20. PolyMide CoPA — Technical Data Sheet page Polymaker Wiki · 2026-08 · tds
  21. TECAMID 66 natural (PA66) — stock shape properties Ensinger · 2026-08 · tds
  22. BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · test
  23. 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
  24. Ultramid Nylon Chemical Resistance guide (unmodified PA6 B27E and PA66 A27E) BASF · 2026-08 · tds
  25. Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds