3D Printing Info

Filament comparison

rPLA vs PLA Silk

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

Recycled PLA (rPLA) guideSilk PLA guide

2 selected · all documented properties

Open these two in the interactive comparisonMore rPLA comparisonsMore PLA Silk comparisons
rPLA vs PLA Silk — documented properties and sources
PropertyRecycled PLA (rPLA)PLASilk PLAPLA
Market snapshot
Listing priceUSD/kg; dated snapshots$20.79/kg median; $16.05–$40.64/kg across 8 dated product listings$19.49/kg median; $9.75–$24.99/kg across 15 dated product listings
Identity & Market
Base polymer / chemistryPLA regranulated from post-industrial PLA manufacturing waste; post-consumer feedstock is rare[1][2][3]PLA with a gloss-forming additive package; suppliers publish the composition as polylactic acid only[4]
Densityg/cm³1.24 (ISO 1183)[1]1.27 (ISO 1183)[4]
Typical priceUSD/kg1 kg spools run 20–22[5][6][7]Mainstream 1 kg spools cluster near 20[8][9][10]
Price range across brandsUSD/kg16–41 across brands; Fiberlogy refill 16, Filamentive 750 g 41[11][12]10–25 across brands; CHCKX 10 in a 16-roll bundle, SUNLU 13, LANDU 18, YXPOLYER 20, Polymaker 22, Devil Design 25[13][14][15][16][17]
Market availability1–5Available from several mainstream brands[2][3][7]Stocked by most mainstream brands[8][13][18]
Spool sizes & diameters1.75 and 2.85 mm; 0.75, 0.85 and 1 kg spools plus spool-less refills[19][11][2]1.75 mm; 1 and 1.1 kg spools; dual- and tri-colour coextruded variants[20][21]
Typical applicationsGeneral-purpose printing where the feedstock's recycled content matters more than an exact colour match[2][3]Decorative prints where surface gloss matters more than strength[4]
Diameter tolerance± mm±0.03 guaranteed by Prusa Research today; the 2021 datasheet specified ±0.05, against ±0.02 for virgin Prusament PLA[2][1][22]±0.03 (Bambu Lab)[23]
Printing Parameters
Nozzle temperature°C210 ± 10 (Prusament); 200 ± 15 (Filamentive)[1][3]210–240 — 20 °C above the plain PLA window[4]
Bed temperature°C40–60 (Prusament); up to 60 (Filamentive)[1][3]35–45[4]
Enclosure / chamber requirement1–5Open frame is fine[1][24]Open frame is fine[4][24]
Part cooling fan100 %[1]Fan on[4]
Bed surface & adhesion aidNot documentedCool Plate SuperTack, smooth PEI or textured PEI[4]
Warping tendency1–5None — brim not generally needed[1]None[4]
Bed-adhesion difficulty1–5Sticks to anything[25]Sticks to anything[25]
Overall printing difficulty1–5Beginner — prints on any machine out of the box[1][24]Easy — minor profile tuning; hotter nozzle and slower cap of 250 mm/s[4]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely[24]Brass fine indefinitely[24]
Abrasiveness1–5Non-abrasive[26][24]Non-abrasive[26][24]
Nozzle clog risk1–5Very low[24]Very low[24]
Heat-creep / jam sensitivity1–5Moderate — good heatbreak cooling needed; PLA softens below 60 °C[27]Moderate — good heatbreak cooling needed; PLA softens below 60 °C[27]
Hotend requirementNo special hot-end required[25]No special hot-end required[25]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate — 0.3 % after both 24 h and 7 days at 28 °C / 37 % RH (Prusa Polymers method), against 0.19 % in 7 days for virgin Prusament PLA[1][22]Moderate — 0.40 % saturated at 25 °C / 55 % RH[4]
Equilibrium moisture content at ~50 % RH%0.3 after 24 h and 7 days at 28 °C / 37 % RH (Prusa Polymers method)[1]0.40 saturated at 25 °C / 55 % RH (Bambu Lab)[4]
Drying temperature & timeNot documented55 °C for 8 h in a forced-air dryer, or 65–75 °C for 12 h on an X1 heatbed[4][28]
Symptoms when wetBubbling and popping at the nozzle, stringing, rough surface and weak layers[29]Bubbling and popping at the nozzle, stringing, rough surface and weak layers[29]
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[29]Polymaker rates PLA low-sensitivity — the loss shows as poor layer adhesion and brittle layers rather than a published strength figure[29]
Storage requirementSealed with desiccant below 20 % RH; shelf life at ambient is long[30][25]Sealed with desiccant below 20 % RH; shelf life at ambient is long[30][25]
Mechanical Properties
Tensile strength (XY)MPa49 printed horizontal and 55 printed vertical XZ (ISO 527-1, yield); virgin Prusament PLA gives 51 and 59 by the same method[1][22]33 (printed XY, ISO 527); eSun Silk broke 22 % below the 16-brand PLA mean on identical 4×4 mm bars[4][31]
Young's modulusMPa2100 printed horizontal, 2300 printed vertical XZ (ISO 527-1); virgin Prusament PLA 2300 and 2400[1][22]2130 (printed XY, ISO 527)[4]
Elongation at break%3.1 at yield printed horizontal (ISO 527-1); virgin Prusament PLA 2.9[1][22]2.8 (printed XY, ISO 527) — a quarter of PLA Basic at 12.2[4][30]
Flexural strengthMPa82 printed horizontal, 87 printed vertical XZ (ISO 178); virgin Prusament PLA 83 and 99[1][22]75 (printed XY, ISO 178)[4]
Flexural modulusMPa3100 printed horizontal (ISO 178) — the same as virgin Prusament PLA[1][22]2460 (printed XY, ISO 178)[4]
Charpy impact, notchedkJ/m²Not documented10.3 (printed XY, ISO 179, notched); unnotched 18.5[4]
Other impact dataCharpy unnotched 14.0 printed horizontal (ISO 179-1); virgin Prusament PLA 13[1][22]Not documented
Layer adhesion / Z tensileMPa21 ± 2 (Prusa Polymers interlayer adhesion test); virgin Prusament PLA 17 ± 3 by the same test[1][22]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[4][31][32]
Brittleness1–5Brittle — snaps with little warning[27][26]Brittle — snaps with little warning[4]
Hardness (scale-specific)Shore A / Shore D / Rockwell80 Shore D (Prusa Polymers in-house method); virgin Prusament PLA 81[1][22]Not documented
Creep resistance / sustained load1–5Poor — no recycled-PLA creep data published; virgin PLA sagged from 12 to 18.7–20.3 mm over 5 days at 1.25 kg[33][34]Poor — no silk-specific creep data published; plain PLA sagged from 12 to 18.7–20.3 mm over 5 days at 1.25 kg[33][34]
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)[35][27]Poor — no grade-specific S-N curve; plain printed PLA ran 38 000–49 000 cycles at 30 % of tensile strength (R = 0.2)[35][27]
Elasticity / flexibility1–5Rigid[26]Rigid[4]
Z strength as % of XY%Not documented76 by tensile, 40 by flexural (printed, Bambu Lab)[4]
Thermal Properties
HDT at 0.45 MPa°C55 (ISO 75, 0.45 MPa) — the same as virgin Prusament PLA[1][22]60 (ISO 75, 0.45 MPa)[4]
HDT at 1.8 MPa°C53 (ISO 75, 1.8 MPa); virgin Prusament PLA 55[1][22]56 (ISO 75, 1.8 MPa)[4]
Glass transition (Tg)°CNot documented57 (DSC)[4]
Melting point / Vicat°CNot documented158 peak melt (DSC); Vicat 66 °C[4]
Continuous service temperature°C55 (Filamentive states heat resistance up to 55 °C)[3]50 — a loaded bar begins to move at this temperature (My Tech Fun, eSun eSilk PLA)[32]
Annealing responseNot documented50–55 °C for 6–12 h[4]
Thermal expansion (CTE)µm/m·K96–99 for plain printed PLA (fibre Bragg grating, 25–50 °C); no grade-specific measurement published[36]Not documented
Flammability / UL 94Flammable; no UL 94 rating published by the major brands[30][37]Flammable; no UL 94 rating published by the major brands[30][37]
Environment & Chemical
UV resistance1–5Degrades within weeks outdoors[27][38]Degrades within weeks outdoors[27][38]
Chemical resistanceGood against weak acids, oils and grease; poor against strong acids and alkalis; dissolved by chloroform, THF and hot benzene[37][27]Good 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 service1–5Good — insoluble in water[30]Good — insoluble in water[30]
Food contactFilamentive certifies its rPLA to EN 71-3 and lists it food safe; printed layer grooves still harbour bacteria[3][27]Base resin is food-contact grade, but printed layer grooves harbour bacteria; Prusa advises against food use[27]
Biodegradability / compostabilityIndustrially compostable only — needs sustained 55 °C; not home compostable[3]Industrially compostable only — needs sustained 55 °C; not home compostable[3][27]
RecyclabilityThe feedstock itself; Filamentive uses 50 % post-industrial content and runs a PLA take-back scheme[3][12]Mechanically recyclable; not accepted in household plastic collection[3]
Health & Safety
Fume toxicity1–5Low hazard — minimal VOC and particle emission[39]Low hazard — minimal VOC and particle emission[39]
Hazardous species emittedPrusament rPLA Corn Pigment uses organic waste pigments such as red algae, which give a noticeable scent while printing[2]Not documented
Ventilation / filtration requirement1–5None needed in a normal room[39]None needed in a normal room[39]
Post-Processing
Sanding & machiningWet sanding — dry sanding heats the surface by friction and smears it[38][27]Wet sanding — dry sanding heats the surface by friction and smears it[38][27]
Gluing & solvent weldingSuperglue for most joints; acetone works on some grades depending on additives and colour[2]Cyanoacrylate for most joints; some grades partially dissolve and bond with acetone[27][2]
Vapour / chemical smoothingNo practical vapour smoothing — only chloroform, hot benzene or THF, which are laboratory-only[27]No practical vapour smoothing — only chloroform, hot benzene or THF, which are laboratory-only[27]
Support material pairingNot documentedSupport for PLA (Bambu Lab)[4]
Dimensional accuracy & detailNot documented55° overhangs and 30 mm bridges; gloss hides fine detail and is destroyed by sanding[4]
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.[40]Chloroform: 10 % w/v in 2–4 h at 23 °C, every grade and morphology; THF and DMF only at 65 °C. Laboratory reagents.[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.[40][41]Acetone, ethyl acetate and toluene plasticise it but dissolve <1 % even at 65 °C; submersion in acetone crazes and destroys parts.[40][41]
Solvent welding & smoothing agentChloroform vapour smooths and welds PLA at the cost of tensile strength; acetone does not smooth it at all.[42][41]Chloroform vapour smooths and welds PLA at the cost of tensile strength; acetone does not smooth it at all.[42][41]

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. Prusament PLA Recycled Technical Datasheet v1.0 Prusa Polymers · 2021-12 · tds
  2. Prusament rPLA Corn Pigment 1kg — product page Prusa Research · 2026-08 · vendor
  3. Filamentive PLA (recycled) — product page Filamentive · 2026-08 · vendor
  4. Bambu Filament Technical Data Sheet V1.0 — PLA Silk+ Bambu Lab · 2026-08 · tds
  5. 3D-Fuel ReFuel Recycled PLA 1kg 3D-Fuel · 2026-08 · vendor
  6. Proto-pasta Black Recycled PLA 1kg Proto-pasta · 2026-08 · vendor
  7. Formfutura ReForm rPLA (White) 1kg Filament2Print · 2026-08 · vendor
  8. Panchroma Silk PLA collection Polymaker Shop · 2026-08 · vendor
  9. Spectrum PLA Silk — product listing 3DJake International · 2026-08 · vendor
  10. 3DJake ecoPLA Silk Black 1.75mm 1000g 3DJake International · 2026-08 · vendor
  11. Fiberlogy rPLA Refill Anthracite 850 g 3DJake International · 2026-08 · vendor
  12. Filamentive PLA (rPLA) 750 g CREATE Education · 2026-08 · vendor
  13. Sunlu Silk PLA+ 1.75mm 1kg Sunlu Official Store · 2026-08 · vendor
  14. Bambu Lab PLA Silk 1.75mm 1kg 3D Universe · 2026-08 · vendor
  15. CHCKX 16 Pack Silk Dual Color PLA Filament Bundle CHCKX (Amazon US) · 2026-08 · vendor
  16. YXPOLYER Silk PLA Black&Gold product page YXPOLYER · 2026-08 · vendor
  17. LANDU Silk Tri-Color PLA Filament 1.75 mm 1 kg LANDU (Amazon US) · 2026-08 · vendor
  18. Overture Silk PLA 1.75mm Overture3D · 2026-08 · vendor
  19. Kimya PLA-R 750 g Crea3D · 2026-08 · vendor
  20. eSUN PLA-Silk Magic 1.75mm eSUN Official Store · 2026-08 · vendor
  21. JAYO Silk PLA+ 1.75mm 1.1kg JAYO Official Store · 2026-08 · vendor
  22. Prusament PLA Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  23. PLA Basic — product page Bambu Lab US Store · 2026-08 · vendor
  24. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  25. PLA — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  26. Prusament PLA — material page Prusa Polymers · 2026-08 · doc
  27. PLA — material guide Prusa Knowledge Base · 2026-08 · doc
  28. Filament Drying Recommendations Bambu Lab Wiki · 2026-08 · doc
  29. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  30. Bambu Filament Technical Data Sheet V3.0 — PLA Basic Bambu Lab · 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. BambuLab PLA Basic vs PLA Tough vs PLA-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  34. PolyTerra PLA vs PLA+ — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  35. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  36. Characterization of Thermal Expansion Coefficient of 3D Printing Polymeric Materials Using Fiber Bragg Grating Sensors Materials 17(18):4668 · 2024-09 · 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. 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
  40. Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · 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