3D Printing Info

Filament comparison

PLA Silk vs PSU

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

Silk PLA guidePSU guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PLA Silk comparisonsMore PSU comparisons
PLA Silk vs PSU — documented properties and sources
PropertySilk PLAPLAPSUHIGHTEMP
Market snapshot
Listing priceUSD/kg; dated snapshots$19.49/kg median; $9.75–$24.99/kg across 15 dated product listings$168.00/kg median; $168.00–$168.00/kg across 1 dated product listings
Identity & Market
Base polymer / chemistryPLA with a gloss-forming additive package; suppliers publish the composition as polylactic acid only[1]Polysulfone — the lowest-temperature and cheapest of the sulfone family[2]
Densityg/cm³1.27 (ISO 1183)[1]1.24 (ISO 1183)[2]
Typical priceUSD/kgMainstream 1 kg spools cluster near 20[3][4][5]1 kg-equivalent spools cluster near 250[6]
Price range across brandsUSD/kg10–25 across brands; CHCKX 10 in a 16-roll bundle, SUNLU 13, LANDU 18, YXPOLYER 20, Polymaker 22, Devil Design 25[7][8][9][10][11]168-250 across formats; 250 g spool $42 (168/kg), 500 g $125 (250/kg) — 3DXTech is the only filament supplier found[6]
Market availability1–5Stocked by most mainstream brands[3][7][12]Special order, 1–2 makers worldwide[6]
Spool sizes & diameters1.75 mm; 1 and 1.1 kg spools; dual- and tri-colour coextruded variants[13][14]1.75 mm; 250 g and 500 g spools[6]
Typical applicationsDecorative prints where surface gloss matters more than strength[1]Transparent high-temperature housings, medical trays and hot-water fittings[2]
Diameter tolerance± mm±0.03 (Bambu Lab)[15]Not documented
Printing Parameters
Nozzle temperature°C210–240 — 20 °C above the plain PLA window[1]Not documented
Bed temperature°C35–45[1]120–140 (3DXTech)[2]
Enclosure / chamber requirement1–5Open frame is fine[1][16]Actively heated chamber required[17][18]
Part cooling fanFan on[1]Not documented
Bed surface & adhesion aidCool Plate SuperTack, smooth PEI or textured PEI[1]Not documented
Warping tendency1–5None[1]Not documented
Bed-adhesion difficulty1–5Sticks to anything[19]Not documented
Overall printing difficulty1–5Easy — minor profile tuning; hotter nozzle and slower cap of 250 mm/s[1]Expert / industrial hardware only[17][18]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely[16]Brass fine indefinitely for unfilled grades, but brass softens near these nozzle temperatures — hardened or plated hot ends are the norm[17]
Abrasiveness1–5Non-abrasive[20][16]Non-abrasive when unfilled[2]
Nozzle clog risk1–5Very low[16]Moderate — needs dry filament and a clean nozzle; 3DXTech lists no special nozzle concerns but a mandatory 120 °C pre-dry before every print[21]
Heat-creep / jam sensitivity1–5Moderate — good heatbreak cooling needed; PLA softens below 60 °C[22]Not documented
Hotend requirementNo special hot-end required[19]Not documented
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate — 0.40 % saturated at 25 °C / 55 % RH[1]Not documented
Equilibrium moisture content at ~50 % RH%0.40 saturated at 25 °C / 55 % RH (Bambu Lab)[1]0.30 in 24 h on extruded stock (ASTM D570)[23]
Drying temperature & time55 °C for 8 h in a forced-air dryer, or 65–75 °C for 12 h on an X1 heatbed[1][24]Not documented
Symptoms when wetBubbling and popping at the nozzle, stringing, rough surface and weak layers[25]Not documented
Effect of moisture on strengthPolymaker rates PLA low-sensitivity — the loss shows as poor layer adhesion and brittle layers rather than a published strength figure[25]No dry-versus-conditioned figures are published; 3DXTech mandates a 120 °C, 4 h pre-dry before every print because trapped water flashes to steam at these nozzle temperatures[21]
Storage requirementSealed with desiccant below 20 % RH; shelf life at ambient is long[26][19]Not documented
Mechanical Properties
Tensile strength (XY)MPa33 (printed XY, ISO 527); eSun Silk broke 22 % below the 16-brand PLA mean on identical 4×4 mm bars[1][27]52 (printed XY, ISO 527, 3DXTech); 81 at break on extruded stock (ASTM D638)[2][23]
Young's modulusMPa2130 (printed XY, ISO 527)[1]2100 (printed XY, ISO 527)[2]
Elongation at break%2.8 (printed XY, ISO 527) — a quarter of PLA Basic at 12.2[1][26]8 (printed XY, ISO 527) against 50 on extruded stock — nearly three times PPSU's printed 3 %[2][28][23]
Flexural strengthMPa75 (printed XY, ISO 178)[1]87 (printed XY, ISO 178)[2]
Flexural modulusMPa2460 (printed XY, ISO 178)[1]2050 (printed XY, ISO 178)[2]
Charpy impact, notchedkJ/m²10.3 (printed XY, ISO 179, notched); unnotched 18.5[1]Not documented
Other impact dataNot documentedIzod notched 69 J/m on extruded PSU stock, converted from 1.3 ft-lb/in (ASTM D256)[23]
Layer adhesion / Z tensileMPa25 (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[1][27][29]Not documented
Brittleness1–5Brittle — snaps with little warning[1]Moderate[2]
Hardness (scale-specific)Shore A / Shore D / RockwellNot documentedRockwell M120 on extruded PSU stock (ASTM D785)[23]
Creep resistance / sustained load1–5Poor — no silk-specific creep data published; plain PLA sagged from 12 to 18.7–20.3 mm over 5 days at 1.25 kg[30][31]Good. Ensinger lists high creep resistance as a headline property of extruded PSU stock, which is rated to 173 °C heat deflection at 1.8 MPa[23]
Fatigue / repeated-flex resistance1–5Poor — no grade-specific S-N curve; plain printed PLA ran 38 000–49 000 cycles at 30 % of tensile strength (R = 0.2)[32][22]Not documented
Elasticity / flexibility1–5Rigid[1]Rigid[2]
Z strength as % of XY%76 by tensile, 40 by flexural (printed, Bambu Lab)[1]Not documented
Thermal Properties
HDT at 0.45 MPa°C60 (ISO 75, 0.45 MPa)[1]172 (printed XY, ISO 75 at 0.45 MPa, 3DXTech); 181 on extruded stock, converted from 358 °F at 66 psi[2][23]
HDT at 1.8 MPa°C56 (ISO 75, 1.8 MPa)[1]174 on extruded PSU stock, converted from 345 °F at 264 psi (ASTM D648)[23]
Glass transition (Tg)°C57 (DSC)[1]187 (DSC, 3DXTech) and 185 on extruded stock (ASTM D3418), against 230 for PPSU[2][28][23]
Melting point / Vicat°C158 peak melt (DSC); Vicat 66 °C[1]Not documented
Continuous service temperature°C50 — a loaded bar begins to move at this temperature (My Tech Fun, eSun eSilk PLA)[29]141 long-term service on extruded PSU stock, converted from 285 °F[23]
Annealing response50–55 °C for 6–12 h[1]Not documented
Thermal expansion (CTE)µm/m·KNot documented55.8 (extruded PSU stock, ASTM D696; source states 3.1e-5 in/in/°F)[23]
Flammability / UL 94Flammable; no UL 94 rating published by the major brands[26][33]UL 94 V-0 on extruded PSU stock[23]
Environment & Chemical
UV resistance1–5Degrades within weeks outdoors[22][34]Not documented
Chemical resistanceGood against weak acids, oils and grease; poor against strong acids and alkalis; dissolved by chloroform, THF and hot benzene[33][22]Not documented
Water / humidity resistance in service1–5Good — insoluble in water[26]Not documented
Food contactBase resin is food-contact grade, but printed layer grooves harbour bacteria; Prusa advises against food use[22]Not documented
Biodegradability / compostabilityIndustrially compostable only — needs sustained 55 °C; not home compostable[35][22]Not documented
RecyclabilityMechanically recyclable; not accepted in household plastic collection[35]Not documented
Electrical & ESD propertiesNot documentedSurface resistance above 10¹³ ohm/sq — an insulator (IEC 60093)[2]
Health & Safety
Fume toxicity1–5Low hazard — minimal VOC and particle emission[36]Moderate — measurable VOCs and UFPs, ventilation advised. None of these polymers was in the chamber study, and all are processed far above the temperatures it covered[36]
Ventilation / filtration requirement1–5None needed in a normal room[36]Ventilated room or enclosure recommended[36]
Post-Processing
Sanding & machiningWet sanding — dry sanding heats the surface by friction and smears it[34][22]Not documented
Gluing & solvent weldingCyanoacrylate for most joints; some grades partially dissolve and bond with acetone[22][37]Not documented
Vapour / chemical smoothingNo practical vapour smoothing — only chloroform, hot benzene or THF, which are laboratory-only[22]Not documented
Support material pairingSupport for PLA (Bambu Lab)[1]Not documented
Dimensional accuracy & detail55° overhangs and 30 mm bridges; gloss hides fine detail and is destroyed by sanding[1]Not documented
Solvents & Solubility
Soluble inChloroform: 10 % w/v in 2–4 h at 23 °C, every grade and morphology; THF and DMF only at 65 °C. Laboratory reagents.[38]Chlorinated hydrocarbons — dichloromethane, chloroform — dissolve polysulfone; ketones and esters attack it as well.[39][40]
Softened or crazed byAcetone, ethyl acetate and toluene plasticise it but dissolve <1 % even at 65 °C; submersion in acetone crazes and destroys parts.[38][41]Acetone, MEK, ethyl acetate, benzene and toluene craze or stress-crack it; methanol and isopropanol only marginally.[40][39]
Solvent welding & smoothing agentChloroform vapour smooths and welds PLA at the cost of tensile strength; acetone does not smooth it at all.[42][41]Dichloromethane cement welds PSU and NMP softens residual resin. Both are laboratory reagents.[39]

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. Bambu Filament Technical Data Sheet V1.0 — PLA Silk+ Bambu Lab · 2026-08 · tds
  2. ThermaX PSU Technical Data Sheet v3 3DXTech · 2026-08 · tds
  3. Panchroma Silk PLA collection Polymaker Shop · 2026-08 · vendor
  4. Spectrum PLA Silk — product listing 3DJake International · 2026-08 · vendor
  5. 3DJake ecoPLA Silk Black 1.75mm 1000g 3DJake International · 2026-08 · vendor
  6. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  7. Sunlu Silk PLA+ 1.75mm 1kg Sunlu Official Store · 2026-08 · vendor
  8. Bambu Lab PLA Silk 1.75mm 1kg 3D Universe · 2026-08 · vendor
  9. CHCKX 16 Pack Silk Dual Color PLA Filament Bundle CHCKX (Amazon US) · 2026-08 · vendor
  10. YXPOLYER Silk PLA Black&Gold product page YXPOLYER · 2026-08 · vendor
  11. LANDU Silk Tri-Color PLA Filament 1.75 mm 1 kg LANDU (Amazon US) · 2026-08 · vendor
  12. Overture Silk PLA 1.75mm Overture3D · 2026-08 · vendor
  13. eSUN PLA-Silk Magic 1.75mm eSUN Official Store · 2026-08 · vendor
  14. JAYO Silk PLA+ 1.75mm 1.1kg JAYO Official Store · 2026-08 · vendor
  15. PLA Basic — product page Bambu Lab US Store · 2026-08 · vendor
  16. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  17. Prusament PEI 1010 Technical Datasheet v1.0 Prusa Polymers · 2024-09 · tds
  18. Prusament PEI 1010 — material page Prusa Polymers · 2026-08 · doc
  19. PLA — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  20. Prusament PLA — material page Prusa Polymers · 2026-08 · doc
  21. THERMAX PSU — product page (print recommendations) 3DXTech · 2026-08 · doc
  22. PLA — material guide Prusa Knowledge Base · 2026-08 · doc
  23. TECASON S natural (PSU) — stock shape properties Ensinger · 2026-08 · tds
  24. Filament Drying Recommendations Bambu Lab Wiki · 2026-08 · doc
  25. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  26. Bambu Filament Technical Data Sheet V3.0 — PLA Basic Bambu Lab · 2026-08 · tds
  27. 16 PLA brand comparison test — results spreadsheet My Tech Fun (Igor Gaspar) · 2022-10 · test
  28. ThermaX PPSU Technical Data Sheet v3 3DXTech · 2026-08 · tds
  29. Testing eSun PLA filaments: PLA-ST vs PLA+ vs Silk PLA My Tech Fun (Igor Gaspar) · 2026-08 · test
  30. BambuLab PLA Basic vs PLA Tough vs PLA-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  31. PolyTerra PLA vs PLA+ — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  32. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  33. PolyLite PLA Technical Data Sheet V5.4 Polymaker · 2024-11 · tds
  34. Prusament PLA Technical Data Sheet v1.0 Prusa Polymers · 2018-09 · tds
  35. Filamentive PLA (recycled) — product page Filamentive · 2026-08 · vendor
  36. 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
  37. Prusament rPLA Corn Pigment 1kg — product page Prusa Research · 2026-08 · vendor
  38. Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
  39. Radel PPSU, Veradel PESU, Acudel modified PPSU Design Guide — environmental stress cracking tables Solvay Specialty Polymers · 2026-08 · tds
  40. Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds
  41. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc
  42. 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