Filament comparison
PA blend vs TPU 85A
Compare printing settings, strength, heat resistance, dated prices and sources.
2 selected · all documented properties
| Property | PA6/66 copolymer blendsPA | TPU 85AFLEX |
|---|---|---|
| Market snapshot | ||
| Listing priceUSD/kg; dated snapshots | $65.62/kg median; $62.00–$113.33/kg across 4 dated product listings | $89.89/kg median; $31.99–$106.05/kg across 6 dated product listings |
| Identity & Market | ||
| Base polymer / chemistry | PA6/66 copolymer — a nylon alloy that lowers the melting point and improves printability against straight PA6[1][2] | Soft thermoplastic polyurethane at 82–85 Shore A[3][4][5] |
| Densityg/cm³ | 1.12 (ISO 1183, Polymaker CoPA)[1] | 1.11 (BASF Ultrafuse 85A) to 1.19 (NinjaFlex 85A), ISO 1183 / ASTM D792[5][3] |
| Typical priceUSD/kg | 1 kg-equivalent spools cluster near 65[6][7][8] | 1 kg-equivalent spools span 32–106; the middle of the market is about 90[9][10][3] |
| Price range across brandsUSD/kg | 62–113 across brands; add:north Adura 62, PrimaCreator NylonPower PA6/66 65 at 500 g, Polymaker CoPA 67, 3DXTech AmideX Nylon 6-66 113[6][9][7][8] | 32–106 across brands; Siraya Tech Flex TPU 85A 32 at 1 kg, add:north TPU Pro Matte 85A 72, Recreus Filaflex 82A 90 at 500 g, Proto-pasta Clear Flexible TPU 90, 3DXTech 3DXFLEX 85A 96, NinjaTek NinjaFlex 106[11][9][10][12][3] |
| Market availability1–5 | Available from several mainstream brands[6][9] | Available from several mainstream brands[9][11] |
| Spool sizes & diameters | 1.75 and 2.85 mm; 0.5, 0.75 and 1 kg spools[6][9][7][8] | 1.75, 2.85 and 3 mm; 0.5, 1 and 2 kg spools[9][11][3] |
| Typical applications | General-purpose nylon parts and, unusually, CoPA can support itself if the support is removed before it absorbs moisture[1] | Soft-touch grips, seals, wearables and anything that must compress and rebound[3][4] |
| Printing Parameters | ||
| Nozzle temperature°C | 250–270 (Polymaker CoPA)[1] | 200–220 (BASF Ultrafuse 85A, 210 typical)[5] |
| Bed temperature°C | 25–50 (Polymaker CoPA)[1] | 40 (BASF Ultrafuse 85A)[5] |
| Enclosure / chamber requirement1–5 | Enclosure required (passive) — Polymaker specifies a chamber at ambient temperature[1] | Open frame is fine[5] |
| Bed surface & adhesion aid | Not documented | PEI 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/s | 16 at Polymaker's 200 mm/s cap on a 0.4 mm nozzle at 0.2 mm layer[1][15] | 1.2–3.2 at the 15–40 mm/s BASF specifies on a 0.4 mm nozzle at 0.2 mm layer[5] |
| Warping tendency1–5 | Not documented | None[5] |
| Bed-adhesion difficulty1–5 | Not documented | Sticks to anything — Recreus states its 82A grade has excellent bed adhesion without a heated bed or additives[4] |
| Stringing / oozing tendency1–5 | Not documented | High — drying plus tuning needed[16][14] |
| Overall printing difficulty1–5 | Advanced — enclosure, hardware upgrades, tuning; must be kept below 20 % RH throughout[1][16] | Advanced — enclosure, hardware upgrades, tuning; at this hardness the filament will not push through a Bowden tube[3][4] |
| Extruder requirement | Not documented | Direct drive only. NinjaTek calls its 85A grade ideal for direct-drive extruders and Recreus specifies direct-drive printers for 82A; BASF caps print speed at 15–40 mm/s with a nozzle of 0.4 mm or larger[3][4][5] |
| Hardware Wear & Reliability | ||
| Nozzle hardness required1–4 | Brass fine indefinitely for unfilled grades[17] | Brass fine indefinitely[18] |
| Abrasiveness1–5 | Non-abrasive when unfilled[17] | Non-abrasive[18] |
| Nozzle clog risk1–5 | Very high — frequent jams without careful setup[19][16] | High — jams from moisture, heat creep or particles[16][14] |
| Heat-creep / jam sensitivity1–5 | Not documented | Very high — softens in the cold zone readily; soft filament buckles between the drive gear and the melt zone[14][3] |
| Hotend requirement | Not documented | No special hot-end required, but a direct-drive extruder is (Simplify3D)[13] |
| Moisture Behaviour | ||
| Moisture absorption (hygroscopicity)1–5 | Very high (>2 %) — Polymaker's own wet-state specimens reached 6.16 % moisture content after 48 h immersion at 60 °C[1][16] | Moderate — NinjaTek measures 0.22 % in 24 h (ASTM D570) and BASF specifies a 70 °C dry for at least 5 h[3][5] |
| Equilibrium moisture content at ~50 % RH% | Not documented | 0.22 after 24 h water immersion (NinjaFlex 85A, ASTM D570) — an immersion figure, not an equilibrium moisture content at 50 % RH[3] |
| Drying temperature & time | 100 °C for 8 h (Polymaker CoPA)[1] | 70 °C for at least 5 h in a hot-air dryer or vacuum oven (BASF)[5] |
| Symptoms when wet | Popping 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 strength | Measured 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; wet TPU prints with poor layer adhesion and weak, brittle layers[16] |
| Storage requirement | Polymaker 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 temperature | Polymaker 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)MPa | 78.0 ± 0.7 printed XY dry and 34.3 ± 2.5 wet, ISO 527 (Polymaker CoPA)[1] | 26 ultimate (NinjaFlex 85A, ASTM D638)[3] |
| Young's modulusMPa | 2703 ± 259 printed XY dry and 724 ± 61 wet, ISO 527 (Polymaker CoPA)[1] | 12 (NinjaFlex 85A, ASTM D638) — two orders of magnitude below any rigid filament; NinjaTek's 95A Cheetah reaches 26 by the same method[3][21] |
| Elongation at break% | 12.7 ± 2.1 printed XY dry and 13.2 ± 2.3 wet, ISO 527 (Polymaker CoPA)[1] | 650 at break (Filaflex 82A) and 660 (NinjaFlex 85A); BASF measures 600 in XY and 320 in ZX[4][3][5] |
| Flexural strengthMPa | 109.8 ± 1.3 printed XY dry and 22.6 ± 0.5 wet, ISO 178 (Polymaker CoPA)[1] | Not documented |
| Flexural modulusMPa | 2510 ± 25 printed XY dry and 636 ± 11 wet, ISO 178 (Polymaker CoPA)[1] | Not documented |
| Charpy impact, notchedkJ/m² | 6.9 ± 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 tensileMPa | 45.8 ± 1.5 printed Z dry, falling to 13.7 ± 1.2 wet, ISO 527 (Polymaker CoPA)[1] | Not documented |
| Brittleness1–5 | Tough — absorbs impact, yields before breaking[1] | Very ductile — bends far before failing[3] |
| Hardness (scale-specific)Shore A / Shore D / Rockwell | Shore D 86 and Rockwell 85 (108) — the source does not name the scales on extruded unfilled PA66 stock (ASTM D2240, D785)[22] | 29 Shore D / 85 Shore A (BASF Ultrafuse 85A, ISO 7619-1); 85 Shore A (NinjaFlex, ASTM D2240); 82 A nominal for Filaflex[3][5][4] |
| Creep resistance / sustained load1–5 | Not documented | Poor — no 85A creep test; a printed 95A TPU bar crept from 74.5 to 82.7 mm over 5 days at 1.25 kg, and softer grades creep more[23] |
| Fatigue / repeated-flex resistance1–5 | Excellent — living hinges viable[17] | Excellent — living hinges viable[14] |
| Elasticity / flexibility1–5 | Semi-flexible[19] | Rubbery / highly elastic[3][4] |
| Z strength as % of XY% | 59 dry (45.8 Z against 78.0 XY) and 40 wet, printed[1] | 53 — BASF measures 320 % elongation at break in ZX against 600 % in XY[5] |
| Wear resistance & friction | Not documented | Abrasion 0.08 g mass loss over 10 000 cycles (NinjaFlex, ASTM D4060); 82 mm³ (BASF, ISO 4649)[3][5] |
| Thermal Properties | ||
| HDT at 0.45 MPa°C | 111 (ISO 75, 0.45 MPa, Polymaker CoPA)[1] | Not documented |
| HDT at 1.8 MPa°C | 70 (ISO 75, 1.8 MPa, Polymaker CoPA)[1] | Not documented |
| Glass transition (Tg)°C | 66 (DSC, Polymaker CoPA)[1] | Not documented |
| Melting point / Vicat°C | 189 melting (DSC); Vicat 180, crystallisation 148, decomposition 370 (Polymaker CoPA)[1] | 216 melting (NinjaFlex 85A, DSC)[3] |
| Annealing response | 80 °C for 6 h (Polymaker CoPA)[1] | Not documented |
| Thermal expansion (CTE)µm/m·K | 81.0 on extruded unfilled PA66 stock (ASTM D696; source states 4.5e-5 in/in/°F) — the same chemistry as a PA6/66 copolymer[22] | Not documented |
| Environment & Chemical | ||
| UV resistance1–5 | Not documented | Good — years with some colour shift; Polymaker lists UV exposure among the conditions TPU withstands[14] |
| Chemical resistance | Not documented | Withstands industrial solvents and UV exposure (Polymaker)[14] |
| Water / humidity resistance in service1–5 | Absorbs water, properties shift — 6.16 % uptake cost 56 % of tensile strength and 73 % of modulus[1] | Not documented |
| Food contact | Not documented | Not food safe without specific certification (Polymaker)[14] |
| Biodegradability / compostability | Not documented | Not biodegradable[14] |
| Recyclability | Not documented | Not accepted in household plastic collection[14] |
| Health & Safety | ||
| Fume toxicity1–5 | Moderate — measurable VOCs and UFPs, ventilation advised[24] | Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[24] |
| VOC emission rateµg/min | Up to 180 caprolactam, the dominant VOC from nylon; total VOC reached nearly 200 µg/min, the highest of the nine filaments tested[24] | Not documented |
| Ultrafine-particle emission rateparticles/min | ≈2 × 10⁸ median — low for ultrafine particles despite the highest VOC mass of any filament tested[24] | Not documented |
| Hazardous species emitted | Caprolactam, at up to 180 µg/min from nylon filament — the largest single-VOC emission rate measured in the study[24] | Not documented |
| Ventilation / filtration requirement1–5 | Ventilated room or enclosure recommended[24] | Open a window / occasional ventilation[24] |
| Post-Processing | ||
| Sanding & machining | Not documented | Difficult to sand or smooth; Polymaker limits post-processing to trimming or tumbling[14] |
| Gluing & solvent welding | Not documented | Cyanoacrylate bonds TPU; no common solvent welds it[14] |
| Vapour / chemical smoothing | Not documented | No practical vapour smoothing[14] |
| Support material pairing | CoPA 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 in | Dissolved at 23 °C by formic acid above ~50 %, phenol, m-cresol, 96 % sulphuric acid or hexafluoroisopropanol — laboratory reagents.[25] | DMF, DMSO, NMP and THF dissolve TPU; acetone, MEK and cyclohexanone are partial solvents. All laboratory reagents.[26] |
| Softened or crazed by | Zinc chloride solutions stress-crack it — 10 % marginal, 37 % not resistant; alcoholic calcium chloride dissolves it.[25] | Toluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[26] |
| Solvent welding & smoothing agent | None — nylon's only solvents are formic acid, phenol and HFIP, all of which degrade the part they wet.[25] | 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
- PolyMide CoPA Technical Data Sheet V5.4 (dry and wet status blocks) Polymaker · 2024-11 · tds
- AmideX Nylon 6-66 — product page 3DXTech · 2026-08 · vendor
- NinjaFlex 85A Technical Specifications NinjaTek · 2026-08 · tds
- Filaflex 82A product page (Shore hardness and elongation) Recreus · 2026-08 · vendor
- Ultrafuse TPU 85A Technical Data Sheet (Version 3.0) BASF Forward AM · 2022-08 · tds
- Polymaker product catalogue Polymaker · 2026-08 · vendor
- add:north Adura product page add:north · 2026-08 · vendor
- PrimaCreator SELECT NylonPower PA6/66 product page PrimaCreator · 2026-08 · vendor
- 3DXTech product catalogue 3DXTech · 2026-08 · vendor
- Siraya Tech Flex TPU 85A Filament — product page Siraya Tech · 2026-08 · vendor
- Proto-pasta product catalogue Proto-pasta · 2026-08 · vendor
- add:north TPU Pro Matte 85A product page add:north · 2026-08 · vendor
- Flexible (TPE/TPU) — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
- TPU — material basics Polymaker Wiki · 2026-08 · doc
- Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
- Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
- PA (Nylon) — material basics Polymaker Wiki · 2026-08 · doc
- Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
- Moisture Conditioning — effect on printed nylon properties Polymaker Wiki · 2026-08 · doc
- PolyMide CoPA — Technical Data Sheet page Polymaker Wiki · 2026-08 · tds
- NinjaTek technical specs comparison chart (Cheetah, NinjaFlex, Armadillo, Alloy 910, Nylon 645) NinjaTek · 2026-08 · tds
- TECAMID 66 natural (PA66) — stock shape properties Ensinger · 2026-08 · tds
- BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · test
- 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
- Ultramid Nylon Chemical Resistance guide (unmodified PA6 B27E and PA66 A27E) BASF · 2026-08 · tds
- Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds