3D Printing Info

Filament comparison

PLA Silk vs TPU 98A

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

Silk PLA guideTPU 98A / hard TPU guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PLA Silk comparisonsMore TPU 98A comparisons
PLA Silk vs TPU 98A — documented properties and sources
PropertySilk PLAPLATPU 98A / hard TPUFLEX
Market snapshot
Listing priceUSD/kg; dated snapshots$19.49/kg median; $9.75–$24.99/kg across 15 dated product listings$94.99/kg median; $34.99–$149.99/kg across 3 dated product listings
Identity & Market
Base polymer / chemistryPLA with a gloss-forming additive package; suppliers publish the composition as polylactic acid only[1]Hard thermoplastic polyurethane at 98 Shore A to about 60 Shore D — the rigid end of the TPU range[2][3]
Densityg/cm³1.27 (ISO 1183)[1]1.23 (Fillamentum Flexfill 98A); 1.2 (Extrudr FLEX HARD, ISO 2781)[2][3]
Typical priceUSD/kgMainstream 1 kg spools cluster near 20[4][5][6]1 kg spools cluster near 150[7]
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[8][9][10][11][12]95–150 across brands; Proto-pasta Clear Rigid TPU 95, Push Plastic TPU 100A 150[13][7]
Market availability1–5Stocked by most mainstream brands[4][8][14]Available from several mainstream brands[7][13][3]
Spool sizes & diameters1.75 mm; 1 and 1.1 kg spools; dual- and tri-colour coextruded variants[15][16]1.75 and 2.85 mm; 0.5, 0.75 and 1 kg spools[13][7]
Typical applicationsDecorative prints where surface gloss matters more than strength[1]Drive belts, wheels, snap-fits and bumpers that need to flex but hold shape under load[2]
Diameter tolerance± mm±0.03 (Bambu Lab)[17]Not documented
Printing Parameters
Nozzle temperature°C210–240 — 20 °C above the plain PLA window[1]230–260 (Extrudr FLEX HARD)[3]
Bed temperature°C35–45[1]50–90 (Extrudr FLEX HARD)[3]
Enclosure / chamber requirement1–5Open frame is fine[1][18]Open frame is fine[3]
Part cooling fanFan on[1]0–30 % (Extrudr FLEX HARD)[3]
Bed surface & adhesion aidCool Plate SuperTack, smooth PEI or textured PEI[1]PEI sheet or painter's tape; Polymaker warns TPU can over-stick and advises a glue stick as a release agent[19][20]
Maximum volumetric flow (mm³/s; see test conditions)mm³/sNot documented4.6 (Extrudr FLEX HARD, stated max volumetric speed on a 0.4 mm nozzle)[3]
Warping tendency1–5None[1]None[3]
Bed-adhesion difficulty1–5Sticks to anything[21]Not documented
Overall printing difficulty1–5Easy — minor profile tuning; hotter nozzle and slower cap of 250 mm/s[1]Easy — minor profile tuning; at this hardness the filament pushes like a rigid material[3]
Extruder requirementNot documentedBowden viable at this hardness — Extrudr rates FLEX HARD to 100 mm/s where its soft grades cap lower[3]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely[18]Brass fine indefinitely[3]
Abrasiveness1–5Non-abrasive[22][18]Non-abrasive[3]
Nozzle clog risk1–5Very low[18]Low[23]
Heat-creep / jam sensitivity1–5Moderate — good heatbreak cooling needed; PLA softens below 60 °C[24]Moderate — good heatbreak cooling needed[20]
Hotend requirementNo special hot-end required[21]No special hot-end required, but a direct-drive extruder is (Simplify3D)[19]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate — 0.40 % saturated at 25 °C / 55 % RH[1]Moderate — the TPU family absorbs readily; Extrudr specifies a 12 h dry at 60 °C for FLEX HARD[3][23]
Equilibrium moisture content at ~50 % RH%0.40 saturated at 25 °C / 55 % RH (Bambu Lab)[1]Not documented
Drying temperature & time55 °C for 8 h in a forced-air dryer, or 65–75 °C for 12 h on an X1 heatbed[1][25]60 °C for 12 h (Extrudr FLEX HARD)[3]
Symptoms when wetBubbling and popping at the nozzle, stringing, rough surface and weak layers[23]Bubbling and popping at the nozzle, stringing and a rough surface[23]
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[23]Polymaker groups TPU with the highly hygroscopic materials; no dry-versus-conditioned figures are published[23]
Storage requirementSealed with desiccant below 20 % RH; shelf life at ambient is long[26][21]Sealed with desiccant; often kept in a dryer during the print[23]
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]53.7 at break (Fillamentum Flexfill 98A, DIN 53504)[2]
Young's modulusMPa2130 (printed XY, ISO 527)[1]Not documented
Elongation at break%2.8 (printed XY, ISO 527) — a quarter of PLA Basic at 12.2[1][26]318 at break (Fillamentum Flexfill 98A, DIN 53504); Extrudr FLEX HARD 490 (ISO 527-2)[2][3]
Flexural strengthMPa75 (printed XY, ISO 178)[1]Not documented
Flexural modulusMPa2460 (printed XY, ISO 178)[1]Not documented
Charpy impact, notchedkJ/m²10.3 (printed XY, ISO 179, notched); unnotched 18.5[1]Not documented
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][28]Not documented
Brittleness1–5Brittle — snaps with little warning[1]Very ductile — bends far before failing[2]
Hardness (scale-specific)Shore A / Shore D / RockwellNot documented98 Shore A and 60 Shore D (Fillamentum, ISO 7619-1); Extrudr FLEX HARD 58 Shore D (ISO 868)[2][3]
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[29][30]Poor — no 98A creep test; a printed 95A TPU bar crept from 74.5 to 82.7 mm over 5 days at 1.25 kg[31]
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][24]Excellent — living hinges viable[20]
Elasticity / flexibility1–5Rigid[1]Semi-flexible[2][3]
Z strength as % of XY%76 by tensile, 40 by flexural (printed, Bambu Lab)[1]Not documented
Wear resistance & frictionNot documentedAbrasion 23 mm³ (Fillamentum, ISO 4649 method A) and 26 mm³ (Extrudr FLEX HARD, ISO 4649-A) — the best abrasion figures in the group[2][3]
Thermal Properties
HDT at 0.45 MPa°C60 (ISO 75, 0.45 MPa)[1]Not documented
HDT at 1.8 MPa°C56 (ISO 75, 1.8 MPa)[1]Not documented
Glass transition (Tg)°C57 (DSC)[1]Not documented
Melting point / Vicat°C158 peak melt (DSC); Vicat 66 °C[1]190–210 melting (Extrudr FLEX HARD, ISO 3146-C); Vicat A 140 (ISO 306)[3]
Continuous service temperature°C50 — a loaded bar begins to move at this temperature (My Tech Fun, eSun eSilk PLA)[28]Not documented
Annealing response50–55 °C for 6–12 h[1]Not documented
Flammability / UL 94Flammable; no UL 94 rating published by the major brands[26][33]Not documented
Environment & Chemical
UV resistance1–5Degrades within weeks outdoors[24][34]Good — years with some colour shift; Polymaker lists UV exposure among the conditions TPU withstands[20]
Chemical resistanceGood against weak acids, oils and grease; poor against strong acids and alkalis; dissolved by chloroform, THF and hot benzene[33][24]Withstands industrial solvents and UV exposure (Polymaker)[20]
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[24]Not food safe without specific certification (Polymaker)[20]
Biodegradability / compostabilityIndustrially compostable only — needs sustained 55 °C; not home compostable[35][24]Not biodegradable[20]
RecyclabilityMechanically recyclable; not accepted in household plastic collection[35]Not accepted in household plastic collection[20]
Health & Safety
Fume toxicity1–5Low hazard — minimal VOC and particle emission[36]Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[36]
Ventilation / filtration requirement1–5None needed in a normal room[36]Open a window / occasional ventilation[36]
Post-Processing
Sanding & machiningWet sanding — dry sanding heats the surface by friction and smears it[34][24]Difficult to sand or smooth; Polymaker limits post-processing to trimming or tumbling[20]
Gluing & solvent weldingCyanoacrylate for most joints; some grades partially dissolve and bond with acetone[24][37]Cyanoacrylate bonds TPU; no common solvent welds it[20]
Vapour / chemical smoothingNo practical vapour smoothing — only chloroform, hot benzene or THF, which are laboratory-only[24]No practical vapour smoothing[20]
Support material pairingSupport for PLA (Bambu Lab)[1]Polymaker warns TPU supports are often very difficult to remove[20]
Dimensional accuracy & detail55° overhangs and 30 mm bridges; gloss hides fine detail and is destroyed by sanding[1]Tear strength 170 kN/m (Fillamentum, ISO 34-1) and 175 kN/m (Extrudr FLEX HARD, ISO 34-1B)[2][3]
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]DMF, DMSO, NMP and THF dissolve TPU; acetone, MEK and cyclohexanone are partial solvents. All laboratory reagents.[39]
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][40]Toluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[39]
Solvent welding & smoothing agentChloroform vapour smooths and welds PLA at the cost of tensile strength; acetone does not smooth it at all.[41][40]None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[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. Flexfill TPU 98A Technical Data Sheet Fillamentum · 2019-08 · tds
  3. Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
  4. Panchroma Silk PLA collection Polymaker Shop · 2026-08 · vendor
  5. Spectrum PLA Silk — product listing 3DJake International · 2026-08 · vendor
  6. 3DJake ecoPLA Silk Black 1.75mm 1000g 3DJake International · 2026-08 · vendor
  7. Push Plastic product catalogue Push Plastic · 2026-08 · vendor
  8. Sunlu Silk PLA+ 1.75mm 1kg Sunlu Official Store · 2026-08 · vendor
  9. Bambu Lab PLA Silk 1.75mm 1kg 3D Universe · 2026-08 · vendor
  10. CHCKX 16 Pack Silk Dual Color PLA Filament Bundle CHCKX (Amazon US) · 2026-08 · vendor
  11. YXPOLYER Silk PLA Black&Gold product page YXPOLYER · 2026-08 · vendor
  12. LANDU Silk Tri-Color PLA Filament 1.75 mm 1 kg LANDU (Amazon US) · 2026-08 · vendor
  13. Proto-pasta product catalogue Proto-pasta · 2026-08 · vendor
  14. Overture Silk PLA 1.75mm Overture3D · 2026-08 · vendor
  15. eSUN PLA-Silk Magic 1.75mm eSUN Official Store · 2026-08 · vendor
  16. JAYO Silk PLA+ 1.75mm 1.1kg JAYO Official Store · 2026-08 · vendor
  17. PLA Basic — product page Bambu Lab US Store · 2026-08 · vendor
  18. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  19. Flexible (TPE/TPU) — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  20. TPU — material basics Polymaker Wiki · 2026-08 · doc
  21. PLA — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  22. Prusament PLA — material page Prusa Polymers · 2026-08 · doc
  23. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  24. PLA — material guide Prusa Knowledge Base · 2026-08 · doc
  25. Filament Drying Recommendations Bambu Lab 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. Testing eSun PLA filaments: PLA-ST vs PLA+ vs Silk PLA My Tech Fun (Igor Gaspar) · 2026-08 · test
  29. BambuLab PLA Basic vs PLA Tough vs PLA-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  30. PolyTerra PLA vs PLA+ — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  31. BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · 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. Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds
  40. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc
  41. 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