3D Printing Info

Filament comparison

PA blend vs PLA Silk

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

PA6/66 copolymer blends guideSilk PLA guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PA blend comparisonsMore PLA Silk comparisons
PA blend vs PLA Silk — documented properties and sources
PropertyPA6/66 copolymer blendsPASilk PLAPLA
Market snapshot
Listing priceUSD/kg; dated snapshots$65.62/kg median; $62.00–$113.33/kg across 4 dated product listings$19.49/kg median; $9.75–$24.99/kg across 15 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]PLA with a gloss-forming additive package; suppliers publish the composition as polylactic acid only[3]
Densityg/cm³1.12 (ISO 1183, Polymaker CoPA)[1]1.27 (ISO 1183)[3]
Typical priceUSD/kg1 kg-equivalent spools cluster near 65[4][5][6]Mainstream 1 kg spools cluster near 20[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]10–25 across brands; CHCKX 10 in a 16-roll bundle, SUNLU 13, LANDU 18, YXPOLYER 20, Polymaker 22, Devil Design 25[11][12][13][14][15]
Market availability1–5Available from several mainstream brands[4][10]Stocked by most mainstream brands[7][11][16]
Spool sizes & diameters1.75 and 2.85 mm; 0.5, 0.75 and 1 kg spools[4][10][5][6]1.75 mm; 1 and 1.1 kg spools; dual- and tri-colour coextruded variants[17][18]
Typical applicationsGeneral-purpose nylon parts and, unusually, CoPA can support itself if the support is removed before it absorbs moisture[1]Decorative prints where surface gloss matters more than strength[3]
Diameter tolerance± mmNot documented±0.03 (Bambu Lab)[19]
Printing Parameters
Nozzle temperature°C250–270 (Polymaker CoPA)[1]210–240 — 20 °C above the plain PLA window[3]
Bed temperature°C25–50 (Polymaker CoPA)[1]35–45[3]
Enclosure / chamber requirement1–5Enclosure required (passive) — Polymaker specifies a chamber at ambient temperature[1]Open frame is fine[3][20]
Part cooling fanNot documentedFan on[3]
Bed surface & adhesion aidNot documentedCool Plate SuperTack, smooth PEI or textured PEI[3]
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][21]Not documented
Warping tendency1–5Not documentedNone[3]
Bed-adhesion difficulty1–5Not documentedSticks to anything[22]
Overall printing difficulty1–5Advanced — enclosure, hardware upgrades, tuning; must be kept below 20 % RH throughout[1][23]Easy — minor profile tuning; hotter nozzle and slower cap of 250 mm/s[3]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely for unfilled grades[24]Brass fine indefinitely[20]
Abrasiveness1–5Non-abrasive when unfilled[24]Non-abrasive[25][20]
Nozzle clog risk1–5Very high — frequent jams without careful setup[26][23]Very low[20]
Heat-creep / jam sensitivity1–5Not documentedModerate — good heatbreak cooling needed; PLA softens below 60 °C[27]
Hotend requirementNot documentedNo special hot-end required[22]
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][23]Moderate — 0.40 % saturated at 25 °C / 55 % RH[3]
Equilibrium moisture content at ~50 % RH%Not documented0.40 saturated at 25 °C / 55 % RH (Bambu Lab)[3]
Drying temperature & time100 °C for 8 h (Polymaker CoPA)[1]55 °C for 8 h in a forced-air dryer, or 65–75 °C for 12 h on an X1 heatbed[3][28]
Symptoms when wetPopping and cracking during extrusion, then hard-to-diagnose defects[26]Bubbling and popping at the nozzle, stringing, rough surface and weak layers[23]
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][26]Polymaker rates PLA low-sensitivity — the loss shows as poor layer adhesion and brittle layers rather than a published strength figure[23]
Storage requirementPolymaker states CoPA must always be stored and used below 20 % relative humidity[1]Sealed with desiccant below 20 % RH; shelf life at ambient is long[29][22]
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][30]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]33 (printed XY, ISO 527); eSun Silk broke 22 % below the 16-brand PLA mean on identical 4×4 mm bars[3][31]
Young's modulusMPa2703 ± 259 printed XY dry and 724 ± 61 wet, ISO 527 (Polymaker CoPA)[1]2130 (printed XY, ISO 527)[3]
Elongation at break%12.7 ± 2.1 printed XY dry and 13.2 ± 2.3 wet, ISO 527 (Polymaker CoPA)[1]2.8 (printed XY, ISO 527) — a quarter of PLA Basic at 12.2[3][29]
Flexural strengthMPa109.8 ± 1.3 printed XY dry and 22.6 ± 0.5 wet, ISO 178 (Polymaker CoPA)[1]75 (printed XY, ISO 178)[3]
Flexural modulusMPa2510 ± 25 printed XY dry and 636 ± 11 wet, ISO 178 (Polymaker CoPA)[1]2460 (printed XY, ISO 178)[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]10.3 (printed XY, ISO 179, notched); unnotched 18.5[3]
Layer adhesion / Z tensileMPa45.8 ± 1.5 printed Z dry, falling to 13.7 ± 1.2 wet, ISO 527 (Polymaker CoPA)[1]25 (printed Z, ISO 527), and flexural Z collapses to 30 against 75 in XY; eSun Silk broke at 12.3 kg where twelve of the 16 plain PLAs managed 44.6–61.5 kg[3][31][32]
Brittleness1–5Tough — absorbs impact, yields before breaking[1]Brittle — snaps with little warning[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)[33]Not documented
Creep resistance / sustained load1–5Not documentedPoor — no silk-specific creep data published; plain PLA sagged from 12 to 18.7–20.3 mm over 5 days at 1.25 kg[34][35]
Fatigue / repeated-flex resistance1–5Excellent — living hinges viable[24]Poor — no grade-specific S-N curve; plain printed PLA ran 38 000–49 000 cycles at 30 % of tensile strength (R = 0.2)[36][27]
Elasticity / flexibility1–5Semi-flexible[26]Rigid[3]
Z strength as % of XY%59 dry (45.8 Z against 78.0 XY) and 40 wet, printed[1]76 by tensile, 40 by flexural (printed, Bambu Lab)[3]
Thermal Properties
HDT at 0.45 MPa°C111 (ISO 75, 0.45 MPa, Polymaker CoPA)[1]60 (ISO 75, 0.45 MPa)[3]
HDT at 1.8 MPa°C70 (ISO 75, 1.8 MPa, Polymaker CoPA)[1]56 (ISO 75, 1.8 MPa)[3]
Glass transition (Tg)°C66 (DSC, Polymaker CoPA)[1]57 (DSC)[3]
Melting point / Vicat°C189 melting (DSC); Vicat 180, crystallisation 148, decomposition 370 (Polymaker CoPA)[1]158 peak melt (DSC); Vicat 66 °C[3]
Continuous service temperature°CNot documented50 — a loaded bar begins to move at this temperature (My Tech Fun, eSun eSilk PLA)[32]
Annealing response80 °C for 6 h (Polymaker CoPA)[1]50–55 °C for 6–12 h[3]
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[33]Not documented
Flammability / UL 94Not documentedFlammable; no UL 94 rating published by the major brands[29][37]
Environment & Chemical
UV resistance1–5Not documentedDegrades within weeks outdoors[27][38]
Chemical resistanceNot documentedGood against weak acids, oils and grease; poor against strong acids and alkalis; dissolved by chloroform, THF and hot benzene[37][27]
Water / humidity resistance in service1–5Absorbs water, properties shift — 6.16 % uptake cost 56 % of tensile strength and 73 % of modulus[1]Good — insoluble in water[29]
Food contactNot documentedBase resin is food-contact grade, but printed layer grooves harbour bacteria; Prusa advises against food use[27]
Biodegradability / compostabilityNot documentedIndustrially compostable only — needs sustained 55 °C; not home compostable[39][27]
RecyclabilityNot documentedMechanically recyclable; not accepted in household plastic collection[39]
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[40]Low hazard — minimal VOC and particle emission[40]
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[40]Not documented
Ultrafine-particle emission rateparticles/min≈2 × 10⁸ median — low for ultrafine particles despite the highest VOC mass of any filament tested[40]Not documented
Hazardous species emittedCaprolactam, at up to 180 µg/min from nylon filament — the largest single-VOC emission rate measured in the study[40]Not documented
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[40]None needed in a normal room[40]
Post-Processing
Sanding & machiningNot documentedWet sanding — dry sanding heats the surface by friction and smears it[38][27]
Gluing & solvent weldingNot documentedCyanoacrylate for most joints; some grades partially dissolve and bond with acetone[27][41]
Vapour / chemical smoothingNot documentedNo practical vapour smoothing — only chloroform, hot benzene or THF, which are laboratory-only[27]
Support material pairingCoPA can support itself, but Polymaker warns the support bonds permanently if it absorbs moisture before removal[1]Support for PLA (Bambu Lab)[3]
Dimensional accuracy & detailNot documented55° overhangs and 30 mm bridges; gloss hides fine detail and is destroyed by sanding[3]
Solvents & Solubility
Soluble inDissolved at 23 °C by formic acid above ~50 %, phenol, m-cresol, 96 % sulphuric acid or hexafluoroisopropanol — laboratory reagents.[42]Chloroform: 10 % w/v in 2–4 h at 23 °C, every grade and morphology; THF and DMF only at 65 °C. Laboratory reagents.[43]
Softened or crazed byZinc chloride solutions stress-crack it — 10 % marginal, 37 % not resistant; alcoholic calcium chloride dissolves it.[42]Acetone, ethyl acetate and toluene plasticise it but dissolve <1 % even at 65 °C; submersion in acetone crazes and destroys parts.[43][44]
Solvent welding & smoothing agentNone — nylon's only solvents are formic acid, phenol and HFIP, all of which degrade the part they wet.[42]Chloroform vapour smooths and welds PLA at the cost of tensile strength; acetone does not smooth it at all.[45][44]

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. Bambu Filament Technical Data Sheet V1.0 — PLA Silk+ Bambu Lab · 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. Panchroma Silk PLA collection Polymaker Shop · 2026-08 · vendor
  8. Spectrum PLA Silk — product listing 3DJake International · 2026-08 · vendor
  9. 3DJake ecoPLA Silk Black 1.75mm 1000g 3DJake International · 2026-08 · vendor
  10. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  11. Sunlu Silk PLA+ 1.75mm 1kg Sunlu Official Store · 2026-08 · vendor
  12. Bambu Lab PLA Silk 1.75mm 1kg 3D Universe · 2026-08 · vendor
  13. CHCKX 16 Pack Silk Dual Color PLA Filament Bundle CHCKX (Amazon US) · 2026-08 · vendor
  14. YXPOLYER Silk PLA Black&Gold product page YXPOLYER · 2026-08 · vendor
  15. LANDU Silk Tri-Color PLA Filament 1.75 mm 1 kg LANDU (Amazon US) · 2026-08 · vendor
  16. Overture Silk PLA 1.75mm Overture3D · 2026-08 · vendor
  17. eSUN PLA-Silk Magic 1.75mm eSUN Official Store · 2026-08 · vendor
  18. JAYO Silk PLA+ 1.75mm 1.1kg JAYO Official Store · 2026-08 · vendor
  19. PLA Basic — product page Bambu Lab US Store · 2026-08 · vendor
  20. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  21. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  22. PLA — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  23. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  24. PA (Nylon) — material basics Polymaker Wiki · 2026-08 · doc
  25. Prusament PLA — material page Prusa Polymers · 2026-08 · doc
  26. Moisture Conditioning — effect on printed nylon properties Polymaker Wiki · 2026-08 · doc
  27. PLA — material guide Prusa Knowledge Base · 2026-08 · doc
  28. Filament Drying Recommendations Bambu Lab Wiki · 2026-08 · doc
  29. Bambu Filament Technical Data Sheet V3.0 — PLA Basic Bambu Lab · 2026-08 · tds
  30. PolyMide CoPA — Technical Data Sheet page Polymaker Wiki · 2026-08 · tds
  31. 16 PLA brand comparison test — results spreadsheet My Tech Fun (Igor Gaspar) · 2022-10 · test
  32. Testing eSun PLA filaments: PLA-ST vs PLA+ vs Silk PLA My Tech Fun (Igor Gaspar) · 2026-08 · test
  33. TECAMID 66 natural (PA66) — stock shape properties Ensinger · 2026-08 · tds
  34. BambuLab PLA Basic vs PLA Tough vs PLA-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  35. PolyTerra PLA vs PLA+ — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  36. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  37. PolyLite PLA Technical Data Sheet V5.4 Polymaker · 2024-11 · tds
  38. Prusament PLA Technical Data Sheet v1.0 Prusa Polymers · 2018-09 · tds
  39. Filamentive PLA (recycled) — product page Filamentive · 2026-08 · vendor
  40. 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
  41. Prusament rPLA Corn Pigment 1kg — product page Prusa Research · 2026-08 · vendor
  42. Ultramid Nylon Chemical Resistance guide (unmodified PA6 B27E and PA66 A27E) BASF · 2026-08 · tds
  43. Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
  44. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc
  45. Effect of vapour smoothing in trichloromethane on 3D printed PLA — surface, mechanical and chemical structure Pitale, Keche & Chopra, Engineering Research Express 6(4) 045579 · 2024-12 · paper