3D Printing Info

Filament comparison

PLA vs TPU soft

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

PLA (standard) guideSoft TPU (below 85A) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PLA comparisonsMore TPU soft comparisons
PLA vs TPU soft — documented properties and sources
PropertyPLA (standard)PLASoft TPU (below 85A)FLEX
Market snapshot
Listing priceUSD/kg; dated snapshots$19.74/kg median; $9.99–$32.99/kg across 24 dated product listings$114.04/kg median; $109.80–$122.27/kg across 4 dated product listings
Identity & Market
Base polymer / chemistryPoly(lactic acid), a thermoplastic aliphatic polyester from fermented plant starch[1][2]Very soft thermoplastic elastomers below 85 Shore A. Fiberlogy's FiberFlex 30D measures 81 Shore A, the softest grade with a published datasheet found here[3]
Densityg/cm³1.17–1.24 (ISO 1183)[1][4][2]1.07 (Fiberlogy FiberFlex 30D, ISO 1183)[3]
Typical priceUSD/kgMainstream 1 kg spools cluster near 20[5][6][7]1 kg-equivalent spools cluster near 115[8][9][10]
Price range across brandsUSD/kg10–33 across brands; budget house brands 10–14, premium European 26–33[11][12][13][14]110–122 at 1 kg-equivalent; Recreus 70A 110 and 60A 116 at 500 g, NinjaTek Edge 83A 112, NinjaTek Chinchilla 75A 122; the Recreus 3 kg spools fall to 70–73[8][10][9]
Market availability1–5Ubiquitous, every brand and retailer[15][16]Niche, a handful of specialist brands[3][17][8]
Spool sizes & diameters1.75 and 2.85 mm; 0.75, 0.85, 1 and 1.1 kg spools plus spool-less refills[5][18][19][13][20]1.75, 2.85 and 3 mm; 0.5, 0.85, 1, 2 and 3 kg spools[3][8][21][9]
Typical applicationsConcept models, functional prototypes, low-wear toys, jigs used at room temperature[22]Highly compliant seals, soft grips and prosthetic liners[3]
Diameter tolerance± mm±0.02 (Prusament) to ±0.03 (Bambu Lab, Prusa Research standard)[1][5][23]Not documented
Printing Parameters
Nozzle temperature°C190–230; Prusament specifies 210 ± 10[1][4][2]Not documented
Bed temperature°C25–60; Prusament 40–60, Bambu Lab 35–45[1][4][2]50–70 (Fiberlogy FiberFlex 30D)[3]
Enclosure / chamber requirement1–5Open frame is fine[4][15]Open frame is fine[3]
Part cooling fan100 % from the second layer; reduce on the first one or two layers for bed adhesion[1][16]Not documented
Bed surface & adhesion aidSmooth or textured PEI, glass or painter's tape; glue stick only where release is a problem[4][24][16]PEI sheet or painter's tape; Polymaker warns TPU can over-stick and advises a glue stick as a release agent[25][26]
Maximum volumetric flow (mm³/s; see test conditions)mm³/s12–20 (PrusaSlicer max volumetric speed guidance for PLA)[27]Not documented
Warping tendency1–5None[28][15]Not documented
Bed-adhesion difficulty1–5Sticks to anything — glue only needed on smooth PEI[4][2][16]Not documented
Stringing / oozing tendency1–5Slight — 1–3 mm retraction handles it; oozing rises with nozzle temperature[4][16][29]Not documented
Overall printing difficulty1–5Beginner — prints on any machine out of the box[15][16]Expert / industrial hardware only — below 85 Shore A the filament buckles in almost any feed path that is not a short, constrained direct drive[21][26]
Extruder requirementAny extruder; Bowden and direct drive both fine, no hardware upgrades[15]Direct drive only, with a constrained filament path; Bowden is not viable at this hardness[21][17]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely[15]Brass fine indefinitely[30]
Abrasiveness1–5Non-abrasive[28][15]Non-abrasive[30]
Nozzle clog risk1–5Very low[15][16]High — jams from moisture, heat creep or particles; below 85 Shore A the filament buckles and compresses, and Simplify3D warns that raised feed rates most likely end in a jam[25][26][31]
Heat-creep / jam sensitivity1–5Moderate — good heatbreak cooling needed; softens below 60 °C so it deforms in a warm cold zone[24][32]Very high — softens in the cold zone readily[26]
Hotend requirementAny standard hotend; PTFE-lined is fine at PLA temperatures[15]No special hot-end required, but a direct-drive extruder is (Simplify3D)[25]
Other hardware wearNone — brass nozzles and standard drive gears are unaffected[28][15]Not documented
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate — 0.40–0.51 % saturated at 23–25 °C and 55–70 % RH[2][4][33]Moderate[31]
Equilibrium moisture content at ~50 % RH%0.43 saturated at 25 °C / 55 % RH (Bambu Lab); 0.51 equilibrium (Polymaker)[2][4]Not documented
Drying temperature & time50–55 °C for 6–8 h in a forced-air dryer; 45 °C for 12 h in the Bambu Lab AMS HT[4][2][32]Not documented
Symptoms when wetBubbling and popping at the nozzle, stringing, rough surface and weak layers[31]Bubbling and popping at the nozzle, stringing and a rough surface[31]
Effect of moisture on strengthPolymaker rates PLA low-sensitivity — it absorbs moisture slowly and the loss shows as poor layer adhesion and brittle layers rather than a published strength figure[31]Polymaker groups TPU with the highly hygroscopic materials; no dry-versus-conditioned figures are published[31]
Storage requirementSealed with desiccant below 20 % RH; shelf life at ambient is long[2][16]Sealed with desiccant; often kept in a dryer during the print[31]
Mechanical Properties
Tensile strength (XY)MPa35–52 (printed XY, ISO 527); 55 mean across 16 brands and 53 for the reference PLA in a later run, both on 4×4 mm printed bars[1][4][2][34][35]Not documented
Young's modulusMPa2300–3427 (printed XY, ISO 527)[1][4][2]Not documented
Elongation at break%6.3–12.2 (printed XY, ISO 527); Prusament quotes 2.9 at yield[4][2][1]870 at break (Fiberlogy FiberFlex 30D, ISO 527) — the highest elongation in the dataset[3]
Flexural strengthMPa76–87 (printed XY, ISO 178); Fiberlogy quotes 81 by ASTM D790[1][4][2][36]Not documented
Flexural modulusMPa2750–3230 (printed XY, ISO 178); Fiberlogy quotes 3800 by ASTM D790[1][4][2][36]Not documented
Charpy impact, notchedkJ/m²3.3–7.9 (printed XY, ISO 179, notched)[4][2]Not documented
Other impact dataCharpy unnotched, printed: 13–14 (Prusament, ISO 179-1), 26.6 (Bambu Lab PLA Basic)[1][2]Not documented
Layer adhesion / Z tensileMPa17–31 (Prusa interlayer test and printed Z tensile); 23 mean on My Tech Fun 4×4 mm bars[1][2][35]Not documented
Brittleness1–5Brittle — snaps with little warning[24][28]Very ductile — bends far before failing[3]
Hardness (scale-specific)Shore A / Shore D / Rockwell81 Shore D (Prusa Polymers in-house method); 75.3 Shore D measured on printed bars (My Tech Fun, Sunlu PLA)[1][37]81 Shore A and 30 Shore D (Fiberlogy FiberFlex 30D, ISO 7619)[3]
Creep resistance / sustained load1–5Poor — deforms under load at room temperature; 12 mm bar sagged to 20.3 mm over 5 days at 1.25 kg[38][39]Poor — no creep test at this hardness; a printed 95A TPU bar crept from 74.5 to 82.7 mm over 5 days at 1.25 kg[40]
Fatigue / repeated-flex resistance1–5Poor — 38 000–49 000 cycles at 30 % of tensile strength, against 79 000–193 000 for PETG (printed, R = 0.2, 7 Hz)[41][24]Excellent — living hinges viable[26]
Elasticity / flexibility1–5Rigid[28]Rubbery / highly elastic[3]
Z strength as % of XY%77–89 on TDS specimens; ≈44 on My Tech Fun 4×4 mm bars[4][2][35]Not documented
Wear resistance & frictionNot documentedTear strength 95 kN/m (Fiberlogy FiberFlex 30D, ISO 34-1)[3]
Thermal Properties
HDT at 0.45 MPa°C55–60 (ISO 75, 0.45 MPa)[1][4][2]Not documented
HDT at 1.8 MPa°C54–58 (ISO 75, 1.8 MPa)[1][4][2]Not documented
Glass transition (Tg)°C55–61 (DSC)[1][4][2]Not documented
Melting point / Vicat°C145–160 peak melt (Prusament, ISO 11357); 150 and 160 by DSC (PolyLite, Bambu Lab); Vicat 57–63 (ISO 306)[22][4][2]170 melting (Fiberlogy FiberFlex 30D, DSC)[3]
Continuous service temperature°C50–55 — loaded bars begin to move at this temperature[28][35]Not documented
Annealing responseBambu Lab conditions specimens at 55 °C for 8 h; annealing at 50–60 °C for 6–12 h raises crystallinity but can warp parts[2][42]Not documented
Thermal expansion (CTE)µm/m·K96 ± 5 at 0° and 99 ± 5 at 90° raster (printed PLA, fibre Bragg grating, 25–50 °C)[43]Not documented
Flammability / UL 94Flammable; no UL 94 rating published by the major brands[2][4]Not documented
Environment & Chemical
UV resistance1–5Degrades within weeks outdoors[24][22]Good — years with some colour shift; Polymaker lists UV exposure among the conditions TPU withstands[26]
Outdoor durabilityNot suitable for long-term outdoor use — UV embrittlement plus softening above 55 °C in direct sun[22][24]Not documented
Chemical resistanceGood against weak acids, oils and grease; poor against strong acids and alkalis; dissolved by chloroform, THF and hot benzene[4][24]Withstands industrial solvents and UV exposure (Polymaker)[26]
Water / humidity resistance in service1–5Good — insoluble in water, absorbs 0.4–0.5 % at equilibrium[2][44]Not documented
Food contactBase resin is food-contact grade and EN 71-3 certified by some brands, but printed layer grooves harbour bacteria; Prusa advises against food use[24][44]Not food safe without specific certification (Polymaker)[26]
Biodegradability / compostabilityIndustrially compostable only — needs sustained 55 °C and specific microbial conditions; not home compostable[44][24][2]Not biodegradable[26]
RecyclabilityMechanically recyclable; not accepted in household plastic collection, so brand take-back schemes are the practical route[44]Not accepted in household plastic collection[26]
Health & Safety
Fume toxicity1–5Low hazard — minimal VOC and particle emission[45]Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[45]
VOC emission rateµg/min4–5 lactide, the dominant VOC (chamber study, three printers)[45]Not documented
Ultrafine-particle emission rateparticles/min≈1 × 10⁸ median across three printers; only laywood ≈8 × 10⁷ and laybrick ≈6 × 10⁷ were lower[45]Not documented
Hazardous species emittedLactide (3,6-dimethyl-1,4-dioxane-2,5-dione) dominates; no styrene or caprolactam as a leading species[45]Not documented
Ventilation / filtration requirement1–5None needed in a normal room[45]Open a window / occasional ventilation[45]
Post-Processing
Sanding & machiningWet sanding — dry sanding heats the surface by friction and smears it[22][24]Difficult to sand or smooth; Polymaker limits post-processing to trimming or tumbling[26]
Gluing & solvent weldingCyanoacrylate for most joints; some grades partially dissolve and bond with acetone, depending on additives and colour[24][23]Cyanoacrylate bonds TPU; no common solvent welds it[26]
Vapour / chemical smoothingNo practical vapour smoothing — only chloroform, hot benzene or THF, which are laboratory-only[24]No practical vapour smoothing[26]
Support material pairingPolySupport and PolyDissolve S1 (Polymaker); Support for PLA (Bambu Lab)[4][2]Polymaker warns TPU supports are often very difficult to remove[26]
Dimensional accuracy & detailGood — low shrinkage and features under 0.2 mm resolve; 55° overhangs and 30 mm bridges[28][2][16]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.[46]DMF, DMSO, NMP and THF dissolve TPU; acetone, MEK and cyclohexanone are partial solvents. All laboratory reagents.[47]
Softened or crazed byAcetone, ethyl acetate and toluene plasticise it but dissolve <1 % even at 65 °C; submersion in acetone crazes and destroys parts.[46][48]Toluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[47]
Solvent welding & smoothing agentChloroform vapour smooths and welds PLA at the cost of tensile strength; acetone does not smooth it at all.[49][48]None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[47]

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 Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  2. Bambu Filament Technical Data Sheet V3.0 — PLA Basic Bambu Lab · 2026-08 · tds
  3. FiberFlex 30D Technical Data Sheet Fiberlogy · 2026-08 · tds
  4. PolyLite PLA Technical Data Sheet V5.4 Polymaker · 2024-11 · tds
  5. PLA Basic — product page Bambu Lab US Store · 2026-08 · vendor
  6. MH Build Series PLA Filament White 1.75mm 1kg MatterHackers · 2026-08 · vendor
  7. 3DJAKE ecoPLA Black 1.75mm 1000g 3DJake International · 2026-08 · vendor
  8. Recreus product catalogue Recreus · 2026-08 · vendor
  9. Chinchilla product page — print guidelines, spool sizes and price NinjaTek · 2026-08 · vendor
  10. NinjaFlex Edge product page — durometer, print guidelines and price NinjaTek · 2026-08 · vendor
  11. JAYO PLA Classic 1.1KG 1.75mm JAYO Official Store · 2026-08 · vendor
  12. ELEGOO PLA Filament 1.75mm Colored 1KG Elegoo US Official Store · 2026-08 · vendor
  13. Fillamentum PLA Extrafill Natural 1kg Fillamentum USA · 2026-08 · vendor
  14. Prusament PLA Jet Black 1kg (NFC) Prusa Research · 2026-08 · vendor
  15. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  16. PLA — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  17. Filaflex 82A product page (Shore hardness and elongation) Recreus · 2026-08 · vendor
  18. Fiberlogy rPLA Refill Anthracite 850 g 3DJake International · 2026-08 · vendor
  19. JAYO Silk PLA+ 1.75mm 1.1kg JAYO Official Store · 2026-08 · vendor
  20. ColorFabb PLA/PHA 750g 3D Universe · 2026-08 · vendor
  21. NinjaFlex 85A Technical Specifications NinjaTek · 2026-08 · tds
  22. Prusament PLA Technical Data Sheet v1.0 Prusa Polymers · 2018-09 · tds
  23. Prusament rPLA Corn Pigment 1kg — product page Prusa Research · 2026-08 · vendor
  24. PLA — material guide Prusa Knowledge Base · 2026-08 · doc
  25. Flexible (TPE/TPU) — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  26. TPU — material basics Polymaker Wiki · 2026-08 · doc
  27. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  28. Prusament PLA — material page Prusa Polymers · 2026-08 · doc
  29. PLA — material basics Polymaker Wiki · 2026-08 · doc
  30. Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
  31. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  32. Filament Drying Recommendations Bambu Lab Wiki · 2026-08 · doc
  33. PolySonic PLA Technical Data Sheet V5.4 Polymaker · 2024-11 · tds
  34. 16 PLA brand comparison test — results spreadsheet My Tech Fun (Igor Gaspar) · 2022-10 · test
  35. Creality Hyper PLA filament review — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  36. Easy PLA — product and technical data Fiberlogy · 2026-08 · tds
  37. Carbon Fiber PLA vs META-PLA vs PLA+ vs PLA by Sunlu — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  38. BambuLab PLA Basic vs PLA Tough vs PLA-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  39. PolyTerra PLA vs PLA+ — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  40. BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · test
  41. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  42. Bambu Filament Technical Data Sheet V3.0 — PLA Matte Bambu Lab · 2026-08 · tds
  43. Characterization of Thermal Expansion Coefficient of 3D Printing Polymeric Materials Using Fiber Bragg Grating Sensors Materials 17(18):4668 · 2024-09 · paper
  44. Filamentive PLA (recycled) — product page Filamentive · 2026-08 · vendor
  45. 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
  46. Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
  47. Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds
  48. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc
  49. 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