3D Printing InfoFilament comparison
PA6/66 vs PPA
Compare printing settings, strength, heat resistance, dated prices and sources.
2 selected · all documented properties
| Property | PA66 (Nylon 66)PA | PPA (polyphthalamide)PA |
|---|---|---|
| Market snapshot | ||
| Listing priceUSD/kg; dated snapshots | Not documented | $45.49/kg median; $45.49–$45.49/kg across 1 dated product listings |
| Identity & Market | ||
| Base polymer / chemistry | Polyamide 66, condensed from hexamethylenediamine and adipic acid; melts around 40 °C above PA6[1] | Polyphthalamide — a semi-aromatic polyamide in which aromatic diacid units replace part of the aliphatic backbone; Raise3D and Bambu Lab both label it high-temperature nylon[2][3] |
| Densityg/cm³ | 1.14 (extruded unfilled PA66 stock)[4] | 1.21 (ISO 1183, Siraya Tech Fibreheart PPA)[5] |
| Typical priceUSD/kg | Not documented | One 1 kg listing on the market, at 45[6] |
| Price range across brandsUSD/kg | Not documented | 45 for the only unfilled PPA filament found — Siraya Tech Fibreheart PPA at 1 kg; every other PPA in retail is carbon- or glass-filled[6] |
| 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[7][8] | Special order, 1–2 makers worldwide — Siraya Tech is the only brand found selling unfilled PPA filament[6] |
| Spool sizes & diameters | Not documented | 1.75 mm, 1 kg[6] |
| Typical applications | Not documented | Gears, bearings and tooling that must hold load above the reach of PA6 or PA12, and parts exposed to fuels and industrial chemicals[5] |
| Printing Parameters | ||
| Nozzle temperature°C | Not documented | 280–300 (Siraya Tech)[5] |
| Bed temperature°C | Not documented | 70–80 (Siraya Tech)[5] |
| Enclosure / chamber requirement1–5 | Enclosure required (passive)[1] | Enclosure recommended — Siraya Tech advises an enclosure to hold temperature and limit warping on larger prints[5] |
| Part cooling fan | Not documented | 20–60 % (Siraya Tech)[5] |
| Bed surface & adhesion aid | Not documented | PEI sheet with a glue stick, or a PVP glue coating[5] |
| Overall printing difficulty1–5 | Advanced — enclosure, hardware upgrades, tuning[1] | Advanced — enclosure, hardware upgrades, tuning; needs a 300 °C-class hot end and a dry spool[5] |
| Hardware Wear & Reliability | ||
| Nozzle hardness required1–4 | Not documented | Brass fine indefinitely — Siraya Tech states a hardened steel nozzle is not needed for the unfilled grade[5] |
| Abrasiveness1–5 | Not documented | Non-abrasive when unfilled[5] |
| Nozzle clog risk1–5 | Very high — frequent jams without careful setup[9][10] | Moderate — needs dry filament and a clean nozzle; Siraya Tech tells users to dry only when moisture symptoms appear, rather than before every print[5] |
| Hotend requirement | Not documented | High-quality metal nozzle, 0.4–1.0 mm; hardened steel not required (Siraya Tech)[5] |
| Moisture Behaviour | ||
| Moisture absorption (hygroscopicity)1–5 | Very high (>2 %)[10] | High (0.8–2 %) — Siraya Tech publishes 2.59 % by ISO 62 immersion for the unfilled grade; on the equilibrium basis Bambu Lab uses, its 15 % carbon-filled PPA reaches 1.30 % against 2.35 % for the same maker's PA6-CF[5][3][11] |
| 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] | 2.59 by ISO 62 water immersion (Siraya Tech, unfilled) — an immersion figure, not the 25 °C / 55 % RH equilibrium basis the filled grades are quoted on, so the two are not directly comparable[5] |
| Drying temperature & time | Not documented | 80–100 °C for 4–6 h (Siraya Tech)[5] |
| Symptoms when wet | Not documented | Oozing, bubbles and a rough surface finish (Siraya Tech)[5] |
| 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][9] | Siraya Tech publishes dry against saturated for the same grade: tensile 70 → 60 MPa, flexural 114 → 87 MPa, HDT at 1.8 MPa 73.5 → 48.5 °C, while Charpy rises 10 → 14.5 kJ/m²[5][6] |
| Storage requirement | Not documented | Dry box below 15 % RH (Siraya Tech)[5] |
| 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] | 72 at break (printed, ASTM D638, Siraya Tech); the product page quotes 70 dry and 60 saturated[5][6] |
| Young's modulusMPa | 2413 on extruded PA66 stock (ASTM D638; converted from 350,000 psi)[4] | 3600 (printed, ASTM D638, Siraya Tech)[5] |
| Elongation at break% | 50 at break on extruded PA66 stock (ASTM D638)[4] | 10.5 at break (printed, ASTM D638, Siraya Tech)[5] |
| Flexural strengthMPa | 113.8 on extruded PA66 stock (ASTM D790; converted from 16,500 psi)[4] | 115 (printed, ISO 178, Siraya Tech); 114 dry against 87 saturated on the product page[5][6] |
| Flexural modulusMPa | 3034 on extruded PA66 stock (ASTM D790; converted from 440,000 psi)[4] | 3350 (printed, ISO 178, Siraya Tech)[5] |
| Charpy impact, notchedkJ/m² | Not documented | 10.1 Charpy (printed, ISO 179, Siraya Tech); the data sheet does not state whether the specimen was notched[5] |
| Other impact data | Izod 53 J/m on extruded PA66 stock, converted from 1.0 ft-lb/in (ASTM D256)[4] | Not documented |
| Brittleness1–5 | Not documented | Moderate — 10.5 % elongation at break puts it between PA6 and the fibre-filled grades[5] |
| 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] | Not documented |
| Creep resistance / sustained load1–5 | Not documented | Good — Raise3D cites high creep resistance as a reason to choose the PPA matrix over other nylons[2] |
| Fatigue / repeated-flex resistance1–5 | Excellent — living hinges viable[1] | Not documented |
| Elasticity / flexibility1–5 | Semi-flexible[9] | Rigid — 3.6 GPa tensile modulus[5] |
| 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] | Siraya Tech describes the unfilled grade as low-friction and self-lubricating, aimed at gears and bearings[5][6] |
| Thermal Properties | ||
| HDT at 0.45 MPa°C | 232 on extruded PA66 stock (ASTM D648 at 66 psi; converted from 450 °F)[4] | 81 dry and 61 saturated (printed, ISO 75 Method B at 0.45 MPa, Siraya Tech)[5] |
| 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] | 73.5 dry and 48.5 saturated (printed, ISO 75 Method A at 1.8 MPa, Siraya Tech) — unfilled PPA deflects near its Tg; the 190–227 °C figures quoted for PPA are carbon-filled grades[5][3] |
| Glass transition (Tg)°C | Not documented | 80 (ASTM D3418, Siraya Tech)[5] |
| Melting point / Vicat°C | 255 melting on extruded PA66 stock (ASTM D2133; converted from 491 °F)[4] | 231 melting point (ASTM D3418) and 230 Vicat (ISO 306), Siraya Tech[5] |
| Continuous service temperature°C | 85 long term and 149 short term on extruded PA66 stock (converted from 185 °F and 300 °F)[4] | Not documented |
| Annealing response | Not documented | Siraya Tech's product page offers annealing for strength while its own data sheet says annealing is not recommended because the print can warp; on its 15 % carbon-filled PPA, annealing lifts HDT at 1.8 MPa from 82.5 to 119 °C[5][6][13] |
| Thermal expansion (CTE)µm/m·K | 81.0 (extruded PA66 stock, ASTM D696; source states 4.5e-5 in/in/°F)[4] | Not documented |
| Flammability / UL 94 | UL 94 V-2 on extruded PA66 stock[4] | Not documented |
| Environment & Chemical | ||
| Chemical resistance | Not documented | Withstands fuels, oils and industrial chemicals; Bambu Lab rates semi-aromatic nylon better than general nylon against weak acids, weak alkalis and most organic solvents[5][3] |
| Water / humidity resistance in service1–5 | Not documented | Absorbs water, properties shift — a saturated specimen loses about 15 % of its tensile strength and 25 °C of heat-deflection temperature[5][6] |
| Electrical & ESD properties | Volume resistance 1e15 ohm-cm and dielectric constant 4 on extruded PA66 stock (ASTM D257, D150)[4] | Not documented |
| Health & Safety | ||
| Fume toxicity1–5 | Moderate — measurable VOCs and UFPs, ventilation advised[14] | 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[14] | Not documented |
| Ultrafine-particle emission rateparticles/min | ≈2 × 10⁸ median — low for ultrafine particles despite the highest VOC mass of any filament tested[14] | 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[14] | Not documented |
| Ventilation / filtration requirement1–5 | Ventilated room or enclosure recommended[14] | Not documented |
| Post-Processing | ||
| Support material pairing | Not documented | Compatible with quick-release support materials (Siraya Tech)[5] |
| Solvents & Solubility | ||
| Soluble in | Dissolved at 23 °C by formic acid above ~80 %, phenol, m-cresol, 96 % sulphuric acid or hexafluoroisopropanol — laboratory reagents.[15] | Dissolved at 23 °C by formic acid, phenol, m-cresol, 96 % sulphuric acid or hexafluoroisopropanol — all laboratory reagents.[15] |
| Softened or crazed by | Zinc chloride solutions stress-crack it — 10 % marginal, 37 % not resistant; alcoholic calcium chloride dissolves it.[15] | Mineral acids, oxidants, halogens and zinc chloride solutions attack the amide bond; ordinary solvents do not.[15] |
| Solvent welding & smoothing agent | None — nylon's only solvents are formic acid, phenol and HFIP, all of which degrade the part they wet.[15] | None — nylon's only solvents are formic acid, phenol and HFIP, all of which degrade the part they wet.[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
- Raise3D Industrial PPA CF Technical Data Sheet V2.0 Raise3D · 2022-04 · tds
- Bambu Filament Technical Data Sheet V1.0 — PPA-CF Bambu Lab · 2026-08 · tds
- TECAMID 66 natural (PA66) — stock shape properties Ensinger · 2026-08 · tds
- Siraya Tech Fibreheart PPA Technical Data Sheet Siraya Tech · 2026-08 · tds
- Siraya Tech Fibreheart PPA Filament — product page Siraya Tech · 2026-08 · vendor
- 3DXTech product catalogue 3DXTech · 2026-08 · vendor
- Polymaker product catalogue Polymaker · 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
- Bambu Filament Technical Data Sheet V3.0 — PA6-CF Bambu Lab · 2026-08 · tds
- PolyMide CoPA Technical Data Sheet V5.4 (dry and wet status blocks) Polymaker · 2024-11 · tds
- Siraya Tech Fibreheart PPA-CF Technical Data Sheet Siraya Tech · 2026-08 · 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