Filament comparison
PA6/66 vs POM
Compare printing settings, strength, heat resistance, dated prices and sources.
2 selected · all documented properties
| Property | PA66 (Nylon 66)PA | POM (acetal)ENGINEERING |
|---|---|---|
| Market snapshot | ||
| Listing priceUSD/kg; dated snapshots | Not documented | Not documented |
| Identity & Market | ||
| Base polymer / chemistry | Polyamide 66, condensed from hexamethylenediamine and adipic acid; melts around 40 °C above PA6[1] | Polyoxymethylene, normally the copolymer POM-C. Apium's filament grade is POM-C with antistatic additives; no unfilled POM filament was found on sale[2][3] |
| Densityg/cm³ | 1.14 (extruded unfilled PA66 stock)[4] | 1.41 (extruded POM-C stock)[2] |
| Market availability1–5 | Special order, 1–2 makers worldwide — no unfilled PA66 filament appeared in any catalogue searched, and the 3DXTech nylon range offers PA6, PA12 and a 6/66 copolymer but no straight PA66[5][6] | Special order, 1-2 makers worldwide — Apium sells a POM-C ESD filament through its own shop and states its printers are the only ones able to process POM-C; no POM filament appears in the 3DJAKE or igo3d product sitemaps, at MatterHackers or at Printed Solid[3][7][8][9] |
| Typical applications | Not documented | Gears, bushings, bearings, conveyor and food-machinery parts; Apium markets its POM-C ESD grade for semiconductor insulators, aerospace fasteners and sliding parts[2][3] |
| Printing Parameters | ||
| Enclosure / chamber requirement1–5 | Enclosure required (passive)[1] | Not documented |
| Overall printing difficulty1–5 | Advanced — enclosure, hardware upgrades, tuning[1] | Not documented |
| Extruder requirement | Not documented | Apium states that the adaptive heating system on its industrial machines is what makes POM-C printable, and that no other 3D printer can process it[3] |
| Hardware Wear & Reliability | ||
| Nozzle clog risk1–5 | Very high — frequent jams without careful setup[10][11] | Not documented |
| Moisture Behaviour | ||
| Moisture absorption (hygroscopicity)1–5 | Very high (>2 %)[11] | Low (0.1-0.3 %) — extruded POM-C stock takes up 0.18 % in 24 h and 0.80 % at saturation (ASTM D570)[2] |
| Equilibrium moisture content at ~50 % RH% | 8.5 at saturation on extruded PA66 stock (ASTM D570) — the highest uptake of any polymer in this dataset[4] | Not documented |
| 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 %[12][10] | Not documented |
| Mechanical Properties | ||
| Tensile strength (XY)MPa | 82.7 at yield and 84.8 at break on extruded PA66 stock (ASTM D638; converted from 12,000 and 12,300 psi) — no printed figure exists because no unfilled PA66 filament was found[4] | 66.9 at break and 64.1 at yield (extruded POM-C stock, ASTM D638; converted from 9700 and 9300 psi)[2] |
| Young's modulusMPa | 2413 on extruded PA66 stock (ASTM D638; converted from 350,000 psi)[4] | 2275 (extruded POM-C stock, ASTM D638; converted from 330,000 psi)[2] |
| Elongation at break% | 50 at break on extruded PA66 stock (ASTM D638)[4] | 40 at break and 9 at yield (extruded POM-C stock, ASTM D638)[2] |
| Flexural strengthMPa | 113.8 on extruded PA66 stock (ASTM D790; converted from 16,500 psi)[4] | 89.6 (extruded POM-C stock, ASTM D790; converted from 13,000 psi)[2] |
| Flexural modulusMPa | 3034 on extruded PA66 stock (ASTM D790; converted from 440,000 psi)[4] | 2758 (extruded POM-C stock, ASTM D790; converted from 400,000 psi)[2] |
| Other impact data | Izod 53 J/m on extruded PA66 stock, converted from 1.0 ft-lb/in (ASTM D256)[4] | Izod 53 J/m on extruded POM-C stock, converted from 1.0 ft-lb/in[2] |
| Brittleness1–5 | Not documented | Tough — absorbs impact, yields before breaking; extruded stock elongates 40 % before failing. No printed figure is published[2] |
| Hardness (scale-specific)Shore A / Shore D / Rockwell | Shore D 86 and Rockwell 85 (108) — the source does not name the scales on extruded PA66 stock (ASTM D2240, D785)[4] | Rockwell 86 (and R120) — the source names only the R scale on extruded POM-C stock (ASTM D785)[2] |
| Fatigue / repeated-flex resistance1–5 | Excellent — living hinges viable[1] | Not documented |
| Elasticity / flexibility1–5 | Semi-flexible[10] | Not documented |
| Wear resistance & friction | Wear factor 200e-10 in3*min/(ft*lb*h) on extruded PA66 stock (ASTM D3702); Ensinger lists very good slide and wear properties[4] | Wear factor 65e-10 in3*min/(ft*lb*h) and a dynamic coefficient of friction of 0.21 at 40 psi and 50 fpm (ASTM D3702, extruded stock) — the properties that make acetal the default gear and bushing plastic; Apium lists good sliding properties as the reason for its grade[2][3] |
| Thermal Properties | ||
| HDT at 0.45 MPa°C | 232 on extruded PA66 stock (ASTM D648 at 66 psi; converted from 450 °F)[4] | 158 (extruded POM-C stock, ASTM D648 at 66 psi; converted from 316 °F)[2] |
| HDT at 1.8 MPa°C | 90 on extruded PA66 stock (ASTM D648 at 264 psi; converted from 194 °F) — the gap to the 0.45 MPa figure is the widest in the dataset[4] | 110 (extruded POM-C stock, ASTM D648 at 264 psi; converted from 230 °F)[2] |
| Melting point / Vicat°C | 255 melting on extruded PA66 stock (ASTM D2133; converted from 491 °F)[4] | 165 melting (extruded POM-C stock; converted from 329 °F)[2] |
| Continuous service temperature°C | 85 long term and 149 short term on extruded PA66 stock (converted from 185 °F and 300 °F)[4] | 91 long term and 141 intermittent (extruded POM-C stock; converted from 195 °F and 285 °F)[2] |
| Thermal expansion (CTE)µm/m·K | 81.0 (extruded PA66 stock, ASTM D696; source states 4.5e-5 in/in/°F)[4] | 84.6 (extruded POM-C stock, ASTM D696; source states 4.7e-5 in/in/°F)[2] |
| Flammability / UL 94 | UL 94 V-2 on extruded PA66 stock[4] | UL 94 HB on extruded POM-C stock[2] |
| Environment & Chemical | ||
| Chemical resistance | Not documented | Good chemical resistance, particularly to bases; Apium lists resistance to bases as a headline property[2][3] |
| Water / humidity resistance in service1–5 | Not documented | Good — minor absorption; 0.80 % water at saturation (ASTM D570, extruded stock)[2] |
| Electrical & ESD properties | Volume resistance 1e15 ohm-cm and dielectric constant 4 on extruded PA66 stock (ASTM D257, D150)[4] | Volume resistance 1e14 ohm-cm, dielectric strength 500 V/mil and dielectric constant 3.7 at 60 Hz on extruded stock (ASTM D257, D149, D150); Apium's filament grade adds antistatic agents[2][3] |
| Health & Safety | ||
| Fume toxicity1–5 | Moderate — measurable VOCs and UFPs, ventilation advised[13] | Not documented |
| 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[13] | Not documented |
| Ultrafine-particle emission rateparticles/min | ≈2 × 10⁸ median — low for ultrafine particles despite the highest VOC mass of any filament tested[13] | 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[13] | Not documented |
| Ventilation / filtration requirement1–5 | Ventilated room or enclosure recommended[13] | Not documented |
| Post-Processing | ||
| Sanding & machining | Not documented | Easy to machine — Ensinger lists machinability as a headline property of POM-C stock[2] |
| Solvents & Solubility | ||
| Soluble in | Dissolved at 23 °C by formic acid above ~80 %, phenol, m-cresol, 96 % sulphuric acid or hexafluoroisopropanol — laboratory reagents.[14] | Hexafluoroisopropanol dissolves it at room temperature; NMP and DMF only when hot. Laboratory reagents.[15] |
| Softened or crazed by | Zinc chloride solutions stress-crack it — 10 % marginal, 37 % not resistant; alcoholic calcium chloride dissolves it.[14] | Acids, oxidants, halogens and hot concentrated zinc chloride attack it; alcohols, ketones and esters do not.[15][16] |
| Solvent welding & smoothing agent | None — nylon's only solvents are formic acid, phenol and HFIP, all of which degrade the part they wet.[14] | None — no solvent softens POM below its melting point, which is why it is bolted or heat-welded rather than glued.[15] |
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
- PA (Nylon) — material basics Polymaker Wiki · 2026-08 · doc
- TECAFORM AH natural (POM-C) — stock shape properties Ensinger · 2026-08 · tds
- POM-C ESD 3D printing — material page Apium 3D Technologies · 2026-08 · doc
- TECAMID 66 natural (PA66) — stock shape properties Ensinger · 2026-08 · tds
- 3DXTech product catalogue 3DXTech · 2026-08 · vendor
- Polymaker product catalogue Polymaker · 2026-08 · vendor
- 3DJAKE product catalogue 3DJAKE · 2026-08 · vendor
- igo3d product sitemap (17452 product URLs) igo3d · 2026-08 · vendor
- Printed Solid product catalogue Printed Solid · 2026-08 · vendor
- Moisture Conditioning — effect on printed nylon properties Polymaker Wiki · 2026-08 · doc
- Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
- PolyMide CoPA Technical Data Sheet V5.4 (dry and wet status blocks) Polymaker · 2024-11 · tds
- 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
- Resistance of Ultramid, Ultraform and Ultradur to chemicals (TI-KTU/AS-28 e) BASF · 2000-10 · tds
- Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds