3D Printing Info

Filament comparison

PVB vs TPU soft

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

PVB guideSoft TPU (below 85A) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PVB comparisonsMore TPU soft comparisons
PVB vs TPU soft — documented properties and sources
PropertyPVBSPECIALTYSoft TPU (below 85A)FLEX
Market snapshot
Listing priceUSD/kg; dated snapshots$66.65/kg median; $49.32–$79.98/kg across 3 dated product listings$114.04/kg median; $109.80–$122.27/kg across 4 dated product listings
Identity & Market
Base polymer / chemistryPolyvinyl butyral — a printable thermoplastic whose surface can be smoothed with isopropyl alcohol instead of a hot solvent[1]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[2]
Densityg/cm³1.10 (Polymaker PolySmooth, ISO 1183); Prusament PVB 1.10[1][3]1.07 (Fiberlogy FiberFlex 30D, ISO 1183)[2]
Typical priceUSD/kg1 kg-equivalent spools cluster near 80[4][5]1 kg-equivalent spools cluster near 115[6][7][8]
Price range across brandsUSD/kg49–102 across brands; Polymaker PolySmooth 49 at 750 g, Prusament PVB 80–102 at 500 g[4][5]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[6][8][7]
Market availability1–5Available from several mainstream brands[4][5]Niche, a handful of specialist brands[2][9][6]
Spool sizes & diameters1.75 and 2.85 mm; 0.5 and 0.75 kg spools[4][5]1.75, 2.85 and 3 mm; 0.5, 0.85, 1, 2 and 3 kg spools[2][6][10][7]
Typical applicationsDisplay models and light guides where a layer-free surface matters more than strength[1]Highly compliant seals, soft grips and prosthetic liners[2]
Diameter tolerance± mm+/- 0.03 (Prusament PVB)[3]Not documented
Printing Parameters
Nozzle temperature°C215 +/- 10 (Prusament PVB)[3]Not documented
Bed temperature°C75 +/- 5 (Prusament PVB)[3]50–70 (Fiberlogy FiberFlex 30D)[2]
Enclosure / chamber requirement1–5Open frame is fine[1]Open frame is fine[2]
Part cooling fan100 % part cooling (Prusament PVB)[3]Not documented
Bed surface & adhesion aidSmooth PEI sheet or satin sheet; Prusa states a brim is not generally necessary[3]PEI sheet or painter's tape; Polymaker warns TPU can over-stick and advises a glue stick as a release agent[11][12]
Overall printing difficulty1–5Easy — minor profile tuning; it prints close to PLA[1]Expert / industrial hardware only — below 85 Shore A the filament buckles in almost any feed path that is not a short, constrained direct drive[10][12]
Extruder requirementNot documentedDirect drive only, with a constrained filament path; Bowden is not viable at this hardness[10][9]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely[1]Brass fine indefinitely[13]
Abrasiveness1–5Non-abrasive[1]Non-abrasive[13]
Nozzle clog risk1–5Moderate — needs dry filament and a clean nozzle; Prusa calls PVB very prone to absorbing moisture and requires a 60 °C, 4 h dry before every print[14][15]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[11][12][15]
Heat-creep / jam sensitivity1–5Not documentedVery high — softens in the cold zone readily[12]
Hotend requirementNot documentedNo special hot-end required, but a direct-drive extruder is (Simplify3D)[11]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Very high (>2 %) — 2.36 % equilibrium water absorption (Polymaker PolySmooth), above every PLA and PETG grade here[1]Moderate[15]
Equilibrium moisture content at ~50 % RH%2.36 equilibrium water absorption (Polymaker PolySmooth); 2.09 for PolyCast; Prusament PVB takes up 0.18 in 24 h and 0.35 in 7 days at 24 °C and 22 % RH[1][16][3]Not documented
Drying temperature & timeMaximum 60 °C for 4-8 h depending on how wet the filament is (Prusament PVB)[3]Not documented
Symptoms when wetNot documentedBubbling and popping at the nozzle, stringing and a rough surface[15]
Effect of moisture on strengthPolymaker publishes no dry-versus-conditioned figures; at 2.36 % equilibrium uptake the material has to be kept dry to print cleanly[1][15]Polymaker groups TPU with the highly hygroscopic materials; no dry-versus-conditioned figures are published[15]
Storage requirementSealed with desiccant[15]Sealed with desiccant; often kept in a dryer during the print[15]
Mechanical Properties
Tensile strength (XY)MPa51.8 ± 0.7 printed XY, ISO 527 (PolySmooth); 53.2 ± 1.1 for PolyCast; Prusament PVB gives 50 +/- 5 at yield printed horizontal (ISO 527-1) and 57 +/- 1 on the filament (ISO 527)[1][16][3]Not documented
Young's modulusMPa2199 ± 43 printed XY and 2010 ± 69 printed Z, ISO 527 (PolySmooth); Prusament PVB gives 1700 +/- 100 in both print directions (ISO 527-1)[1][3]Not documented
Elongation at break%5.7 ± 0.5 printed XY, ISO 527 (PolyCast)[16]870 at break (Fiberlogy FiberFlex 30D, ISO 527) — the highest elongation in the dataset[2]
Flexural strengthMPa72 +/- 1 printed horizontal and 73 +/- 3 printed vertical, ISO 178 (Prusament PVB)[3]Not documented
Flexural modulusMPa2233 ± 106 printed XY, ISO 178 (PolyCast); Prusament PVB gives 2200 +/- 100 horizontal and 2300 +/- 100 vertical (ISO 178)[16][3]Not documented
Charpy impact, notchedkJ/m²7 +/- 1 printed horizontal and 10 +/- 1 printed vertical, ISO 179-1 notched (Prusament PVB)[3]Not documented
Other impact dataCharpy unnotched 55 +/- 7 printed horizontal and 59 +/- 12 printed vertical (Prusament PVB, ISO 179-1)[3]Not documented
Layer adhesion / Z tensileMPa26.3 ± 2.1 printed Z, ISO 527 (PolyCast); Prusament PVB gives 49 +/- 5 at yield printed vertical (ISO 527-1) and 9 +/- 1 on Prusa's interlayer adhesion test[16][3]Not documented
Brittleness1–5Moderate[1]Very ductile — bends far before failing[2]
Hardness (scale-specific)Shore A / Shore D / RockwellShore D 77 (Prusa Polymers method)[3]81 Shore A and 30 Shore D (Fiberlogy FiberFlex 30D, ISO 7619)[2]
Creep resistance / sustained load1–5Not documentedPoor — 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[17]
Fatigue / repeated-flex resistance1–5Not documentedExcellent — living hinges viable[12]
Elasticity / flexibility1–5Rigid[1]Rubbery / highly elastic[2]
Z strength as % of XY%98 (Prusament PVB, printed vertical against horizontal tensile yield, ISO 527-1: 49 +/- 5 against 50 +/- 5) — the most isotropic printed material in this dataset[3]Not documented
Wear resistance & frictionNot documentedTear strength 95 kN/m (Fiberlogy FiberFlex 30D, ISO 34-1)[2]
Thermal Properties
HDT at 0.45 MPa°C68 (PolySmooth) and 67 (PolyCast), ISO 75 at 0.45 MPa; Prusament PVB 63 (ISO 75 at 0.45 MPa)[1][16][3]Not documented
HDT at 1.8 MPa°C66 (PolySmooth) and 53 (PolyCast), ISO 75 at 1.8 MPa; Prusament PVB 58 (ISO 75 at 1.8 MPa)[1][16][3]Not documented
Glass transition (Tg)°C70 (DSC) for both PolySmooth and PolyCast[1][16]Not documented
Melting point / Vicat°CAmorphous — no melting point; Vicat 70 (PolySmooth) and 67 (PolyCast), ISO 306[1][16]170 melting (Fiberlogy FiberFlex 30D, DSC)[2]
Environment & Chemical
UV resistance1–5Not documentedGood — years with some colour shift; Polymaker lists UV exposure among the conditions TPU withstands[12]
Chemical resistanceNot documentedWithstands industrial solvents and UV exposure (Polymaker)[12]
Food contactNot documentedNot food safe without specific certification (Polymaker)[12]
Biodegradability / compostabilityNot documentedNot biodegradable[12]
RecyclabilityNot documentedNot accepted in household plastic collection[12]
Health & Safety
Fume toxicity1–5Low hazard — minimal VOC and particle emission; none of these materials was in the chamber study[18]Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[18]
Ventilation / filtration requirement1–5Open a window / occasional ventilation[18]Open a window / occasional ventilation[18]
Post-Processing
Sanding & machiningNot documentedDifficult to sand or smooth; Polymaker limits post-processing to trimming or tumbling[12]
Gluing & solvent weldingNot documentedCyanoacrylate bonds TPU; no common solvent welds it[12]
Vapour / chemical smoothingIsopropyl alcohol vapour smoothing is the point of the material — Polymaker markets PolySmooth for hands-free post-processing to a layer-free surface[1]No practical vapour smoothing[12]
Support material pairingPolyDissolve S1 is rated for PVB (Polymaker)[19]Polymaker warns TPU supports are often very difficult to remove[12]
Dimensional accuracy & detailPolyCast is the investment-casting variant of the same chemistry — it burns out cleanly rather than being smoothed[16]Not documented
Solvents & Solubility
Soluble inIsopropyl alcohol dissolves it; Prusa describes PVB as soluble only in IPA, and it is not water-soluble.[14]DMF, DMSO, NMP and THF dissolve TPU; acetone, MEK and cyclohexanone are partial solvents. All laboratory reagents.[20]
Softened or crazed byNot documentedToluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[20]
Solvent welding & smoothing agentIsopropyl alcohol: brushed or sprayed on for speed, or several hours in IPA vapour for a glass-like surface.[21][14]None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[20]

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. PolySmooth Technical Data Sheet V5.4 Polymaker · 2024-11 · tds
  2. FiberFlex 30D Technical Data Sheet Fiberlogy · 2026-08 · tds
  3. Prusament PVB Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  4. Polymaker product catalogue Polymaker · 2026-08 · vendor
  5. Printed Solid product catalogue Printed Solid · 2026-08 · vendor
  6. Recreus product catalogue Recreus · 2026-08 · vendor
  7. Chinchilla product page — print guidelines, spool sizes and price NinjaTek · 2026-08 · vendor
  8. NinjaFlex Edge product page — durometer, print guidelines and price NinjaTek · 2026-08 · vendor
  9. Filaflex 82A product page (Shore hardness and elongation) Recreus · 2026-08 · vendor
  10. NinjaFlex 85A Technical Specifications NinjaTek · 2026-08 · tds
  11. Flexible (TPE/TPU) — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  12. TPU — material basics Polymaker Wiki · 2026-08 · doc
  13. Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
  14. Prusament PVB — material page Prusa Polymers · 2026-08 · tds
  15. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  16. PolyCast Technical Data Sheet V5.4 Polymaker · 2024-11 · tds
  17. BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · test
  18. 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
  19. PolyDissolve S1 Technical Data Sheet V5.4 Polymaker · 2024-11 · tds
  20. Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds
  21. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc