3D Printing Info

Filament comparison

PA blend vs rPETG

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

PA6/66 copolymer blends guideRecycled PETG (rPETG) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PA blend comparisonsMore rPETG comparisons
PA blend vs rPETG — documented properties and sources
PropertyPA6/66 copolymer blendsPARecycled PETG (rPETG)PETG
Market snapshot
Listing priceUSD/kg; dated snapshots$65.62/kg median; $62.00–$113.33/kg across 4 dated product listings$28.99/kg median; $17.24–$39.98/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]PETG regranulated from recycled polyester waste; Polymaker's Fiberon PETG-rCF08 adds 8 wt% recycled carbon fibre[3][4][5]
Densityg/cm³1.12 (ISO 1183, Polymaker CoPA)[1]1.27 (Prusament) and 1.30 (Fiberon PETG-rCF08), ISO 1183[3][5]
Typical priceUSD/kg1 kg-equivalent spools cluster near 65[6][7][8]1 kg spools cluster near 29[9][10][6][11]
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[6][9][7][8]17–40 across brands; Filament PM RePETG 17, 3DXTech ECOMAX 26, GreenGate3D 32, Fiberon rCF08 40[9][10][6][11]
Market availability1–5Available from several mainstream brands[6][9]Available from several mainstream brands[9][10][6]
Spool sizes & diameters1.75 and 2.85 mm; 0.5, 0.75 and 1 kg spools[6][9][7][8]1.75 and 2.85 mm; 0.5, 1 and 3 kg spools[6][10]
Typical applicationsGeneral-purpose nylon parts and, unusually, CoPA can support itself if the support is removed before it absorbs moisture[1]Not documented
Diameter tolerance± mmNot documented±0.05 (Prusament PETG Recycled), against ±0.02 for virgin Prusament PETG[3][12]
Printing Parameters
Nozzle temperature°C250–270 (Polymaker CoPA)[1]250 ± 10 (Prusament); 230–255 (Spectrum)[3][4]
Bed temperature°C25–50 (Polymaker CoPA)[1]80 ± 10 (Prusament); 60–80 (Spectrum)[3][4]
Enclosure / chamber requirement1–5Enclosure required (passive) — Polymaker specifies a chamber at ambient temperature[1]Open frame is fine — Spectrum states a closed chamber is not necessary[4]
Part cooling fanNot documented50 % (Prusament); up to 100 % (Spectrum)[3][4]
Bed surface & adhesion aidNot documentedTextured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[12][13]
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][14]Not documented
Bed-adhesion difficulty1–5Not documentedNeeds the right surface or a thin adhesive — the problem is releasing the part, not sticking it[12][13]
Stringing / oozing tendency1–5Not documentedModerate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[13]
Overall printing difficulty1–5Advanced — enclosure, hardware upgrades, tuning; must be kept below 20 % RH throughout[1][15]Easy — minor profile tuning; Spectrum describes printing as similar to standard PETG[4]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely for unfilled grades[16]Brass fine indefinitely[3]
Abrasiveness1–5Non-abrasive when unfilled[16]Not documented
Nozzle clog risk1–5Very high — frequent jams without careful setup[17][15]Low — recycled PETG prints on the same hardware as virgin PETG: no special hot-end, no drybox and no hardened nozzle[18][19]
Heat-creep / jam sensitivity1–5Not documentedSlightly sensitive[18]
Hotend requirementNot documentedNo special hot-end required[18]
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][15]Moderate (0.3–0.8 %) — recycled PETG shares the virgin matrix, which reaches 0.40 % saturated at 25 °C / 55 % RH[12]
Equilibrium moisture content at ~50 % RH%Not documented0.07 after 24 h and 0.10 after 7 days at 24 °C / 22 % RH (Prusa Polymers)[3]
Drying temperature & time100 °C for 8 h (Polymaker CoPA)[1]Not documented
Symptoms when wetPopping and cracking during extrusion, then hard-to-diagnose defects[17]Bubbling and popping at the nozzle, stringing and a rough surface[15]
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][17]Polymaker groups PETG with nylon, PVA and TPU as highly hygroscopic; no dry-versus-conditioned strength figures are published for this grade and the loss shows as bubbling and poor layer adhesion[15]
Storage requirementPolymaker states CoPA must always be stored and used below 20 % relative humidity[1]Sealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[15][13]
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]43 ± 1.8 printed horizontal at yield, ISO 527-1 (Prusament), against 47 ± 2 for virgin Prusament PETG; Spectrum quotes 52 at yield on moulded specimens[3][12][4]
Young's modulusMPa2703 ± 259 printed XY dry and 724 ± 61 wet, ISO 527 (Polymaker CoPA)[1]1500 printed horizontal, 1600 printed vertical (Prusament, ISO 527-1) — the same as virgin Prusament PETG[3][12]
Elongation at break%12.7 ± 2.1 printed XY dry and 13.2 ± 2.3 wet, ISO 527 (Polymaker CoPA)[1]4.5 at yield printed (Prusament); Spectrum quotes 400 at break on moulded specimens[3][4]
Flexural strengthMPa109.8 ± 1.3 printed XY dry and 22.6 ± 0.5 wet, ISO 178 (Polymaker CoPA)[1]63 ± 1 printed horizontal, ISO 178 (Prusament), against 66 ± 2 for virgin Prusament PETG[3][12]
Flexural modulusMPa2510 ± 25 printed XY dry and 636 ± 11 wet, ISO 178 (Polymaker CoPA)[1]1800 printed horizontal, ISO 178 (Prusament)[3]
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]12 ± 1 printed horizontal and 15 ± 3 printed vertical, ISO 179-1 notched (Prusament)[3]
Other impact dataNot documentedCharpy unnotched 25 ± 3 printed horizontal and 38 ± 11 printed vertical (Prusament, ISO 179-1)[3]
Layer adhesion / Z tensileMPa45.8 ± 1.5 printed Z dry, falling to 13.7 ± 1.2 wet, ISO 527 (Polymaker CoPA)[1]15 ± 5 (Prusa Polymers interlayer adhesion test), against 18 ± 4 for virgin Prusament PETG[3][12]
Brittleness1–5Tough — absorbs impact, yields before breaking[1]Moderate[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]74 Shore D (Prusa Polymers method) — the same as virgin Prusament PETG[3][12]
Creep resistance / sustained load1–5Not documentedBelow average — no recycled-grade creep test; virgin PETG sagged from 12 to 17.1–20.4 mm over 5 days at 1.25 kg[22][23][24][25]
Fatigue / repeated-flex resistance1–5Excellent — living hinges viable[16]Moderate — no recycled-grade S-N curve; virgin printed PETG ran 79 000–193 000 cycles at 30 % of tensile strength[26]
Elasticity / flexibility1–5Semi-flexible[17]Slightly flexible in thin sections[3]
Z strength as % of XY%59 dry (45.8 Z against 78.0 XY) and 40 wet, printed[1]Not documented
Thermal Properties
HDT at 0.45 MPa°C111 (ISO 75, 0.45 MPa, Polymaker CoPA)[1]68 (ISO 75, 0.45 MPa) — the same as virgin Prusament PETG; Spectrum quotes 70[3][12][4]
HDT at 1.8 MPa°C70 (ISO 75, 1.8 MPa, Polymaker CoPA)[1]68 (ISO 75, 1.8 MPa)[3]
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]Not documented
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
Flammability / UL 94Not documentedFlammable; no UL 94 rating published for standard grades[27]
Environment & Chemical
Chemical resistanceNot documentedWithstands acids, alkalis, oils and UV exposure[13]
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 certified for food contact as filament[13]
Biodegradability / compostabilityNot documentedNot biodegradable[13]
RecyclabilityNot documentedThe feedstock itself — Spectrum describes collecting, shredding and re-homogenising PETG waste[4]
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[28]Moderate — measurable VOCs and UFPs, ventilation advised[28]
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[28]Not documented
Ultrafine-particle emission rateparticles/min≈2 × 10⁸ median — low for ultrafine particles despite the highest VOC mass of any filament tested[28]Not documented
Hazardous species emittedCaprolactam, at up to 180 µg/min from nylon filament — the largest single-VOC emission rate measured in the study[28]Not documented
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[28]Open a window / occasional ventilation[28]
Post-Processing
Sanding & machiningNot documentedSands poorly — the material is tough and gums rather than powders[18]
Gluing & solvent weldingNot documentedCyanoacrylate; no common solvent welds PETG cleanly[18]
Vapour / chemical smoothingNot documentedNo practical vapour smoothing[18]
Support material pairingCoPA can support itself, but Polymaker warns the support bonds permanently if it absorbs moisture before removal[1]Prints its own supports; Polymaker rates PolyDissolve S1 for PETG[18]
Solvents & Solubility
Soluble inDissolved at 23 °C by formic acid above ~50 %, phenol, m-cresol, 96 % sulphuric acid or hexafluoroisopropanol — laboratory reagents.[29]No common workshop solvent; 1,2-dichloroethane destroys it inside a week and dichloromethane — a carcinogen — dissolves the surface.[30][31]
Softened or crazed byZinc chloride solutions stress-crack it — 10 % marginal, 37 % not resistant; alcoholic calcium chloride dissolves it.[29]Acetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[30]
Solvent welding & smoothing agentNone — nylon's only solvents are formic acid, phenol and HFIP, all of which degrade the part they wet.[29]Dichloromethane brushed on is the only agent that smooths PETG — a controlled carcinogen, not workshop stock.[31]

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. Prusament PETG Recycled Technical Datasheet Prusa Polymers · 2026-08 · tds
  4. Spectrum r-PETG Technical Data Sheet Spectrum Filaments · 2026-08 · tds
  5. Fiberon PETG-rCF08 Technical Data Sheet V1.0 Polymaker · 2026-08 · tds
  6. Polymaker product catalogue Polymaker · 2026-08 · vendor
  7. add:north Adura product page add:north · 2026-08 · vendor
  8. PrimaCreator SELECT NylonPower PA6/66 product page PrimaCreator · 2026-08 · vendor
  9. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  10. GreenGate3D Recycled PET-G — product data GreenGate3D · 2026-08 · vendor
  11. Filament PM RePETG technical data sheet Filament PM (Plasty Mladec) · 2026-08 · tds
  12. Prusament PETG Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  13. PETG — material basics Polymaker Wiki · 2026-08 · doc
  14. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  15. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  16. PA (Nylon) — material basics Polymaker Wiki · 2026-08 · doc
  17. Moisture Conditioning — effect on printed nylon properties Polymaker Wiki · 2026-08 · doc
  18. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  19. Filament Material Guide Prusa Knowledge Base · 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. PCTG vs PETG comparison — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  23. Extrudr PETG vs PCTG vs XPETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  24. Prusament PETG-CF vs PETG V0 vs PETG — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  25. BambuLab PETG Basic vs Translucent vs PETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  26. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  27. Prusament PETG V0 Technical Datasheet Prusa Polymers · 2026-08 · tds
  28. 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
  29. Ultramid Nylon Chemical Resistance guide (unmodified PA6 B27E and PA66 A27E) BASF · 2026-08 · tds
  30. Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
  31. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc