TPU
also Elastollan, Pellethane
TPU is a linear block copolymer of hard (diisocyanate + chain extender) and soft (polyester or polyether polyol) segments, giving rubber-like elasticity with thermoplastic processability by injection moulding, extrusion and FDM printing.
Values for the Shore A 85 condition
TPU grades and fills
TPU is supplied in 19 conditions, soft to hard. Shore A 85 is the default FabDigit quotes; the values on this page are for it.
- Sinterit Flexa Gray
- EOS TPU 1301
- Formlabs TPU 90A
- Forward AM Ultrasint TPU01
- Sinterit Flexa Bright
- Lubrizol ESTANE 3D TPU M88A
- Lubrizol ESTANE 3D TPU M95A
- Shore D 60
- As Printed
- Shore A 70
- FR V-0
- ESD
- Aliphatic
- Ether
- Shore A 85
- Shore A 60 to Shore D 80
- Ester
- GF20
- Shore A 95
Compare all 19 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
SLS powder | 4 | 136 | 70 Shore A | ||
SLS powder | 7 | 250 | 86 Shore A | ||
Formlabs TPU 90A Powder · SLS powder | A tough, skin-safe TPU elastomer for flexible parts requiring high elongation, tear resistance, and everyday durability. | 9 | 310 | 90 Shore A | |
MJF powder | A rubber-like TPU combining elasticity, rebound, fatigue resistance, and shock absorption for durable flexible parts. | 9 | 280 | 88 Shore A | |
SLS powder | 10 | 318 | 79 Shore A | ||
MJF powder | A soft, durable TPU for complex flexible production parts and lattice structures with straightforward cold unpacking. | 15 | 440 | 88 Shore A | |
MJF powder | A durable polyether TPU with high elasticity, abrasion resistance, energy rebound, and skin-contact suitability. | 17 | 400 | 93 Shore A | |
Rigid engineering TPU | Choose for stiff snap-fit housings, wheel cores, chain guides and cable strain relief that must still absorb impact at low temperature. | 25 | 55 | 320 | 60 Shore D |
FDM/FFF printed TPU filament (typ. 95A) | Use for printed flexible prototypes, gaskets and shoe midsoles; expect 60–80 % of injection-moulded strength and Z-direction weakness. | 28 | 380 | 45 Shore D | |
Soft TPU | Pick for soft-touch overmoulds, flexible tubing, bellows and low-durometer seals. | 28 | 680 | 70 Shore A | |
Halogen-free flame-retardant TPU | Specify for cable jackets, connectors and enclosures needing UL 94 V-0 at 1.5–3 mm; some loss of tear strength and elongation. | 28 | 400 | 40 Shore D | |
ESD / antistatic conductive TPU | Use for antistatic hoses, conveyor parts and ESD-safe flexible components in electronics handling. | 30 | 350 | 42 Shore D | |
Aliphatic (HDI/H12MDI) optically clear, non-yellowing TPU | Use for clear films, paint-protection film, safety-glass interlayers and light guides where non-yellowing UV stability is required. | 35 | 500 | 35 Shore D | |
Polyether-based TPU | Choose for wet, humid or microbe-exposed service and for good low-temperature flexibility; slightly lower abrasion/oil performance than ester. | 38 | 600 | 34 Shore D | |
Shore A 85Default Medium-soft general purpose TPU | Default all-round hardness for seals, cable jackets, wheels, grips and flexible parts. | 40 | 550 | 33 Shore D | |
Shore A 60 | Use when the design tolerates any TPU hardness and the exact grade is chosen later by the moulder. | 40 | 500 | 40 Shore D | |
Polyester-based TPU | Best abrasion, tear, oil and fuel resistance at lowest cost — avoid continuous hot/humid or immersed service (hydrolysis). | 45 | 520 | 38 Shore D | |
20 % glass-fibre reinforced TPU | Use where a semi-rigid, dimensionally stable structural part with TPU toughness is needed (housings, wheel hubs, sports hardware). | 45 | 25 | 70 Shore D | |
Hard elastomeric TPU | Pick for load-bearing rollers, couplings, ski boots, hose and abrasion-critical parts needing stiffness with flexibility. | 50 | 480 | 45 Shore D |
Supply forms, finishes and certifications
Ways TPU is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
Medical | Medical / ISO 10993 biocompatible TPU | Certification |
UV | UV-stabilised / weatherable TPU | Grade option |
What is TPU?
TPU is a linear block copolymer of hard (diisocyanate + chain extender) and soft (polyester or polyether polyol) segments, giving rubber-like elasticity with thermoplastic processability by injection moulding, extrusion and FDM printing. It is chosen for outstanding abrasion and tear resistance, oil/grease resistance and a hardness range from Shore A 60 to Shore D 80 without vulcanisation. Main limits are hydrolysis of polyester grades in hot/humid service, creep and compression set versus cast PU or rubber, a modest ~80–100 °C continuous service ceiling, and mandatory pellet drying before processing. TPU has a density of 1.18 g/cm³ (0.0426 lb/in³), heavier than 50% of polymer grades. Its glass-transition temperature is -40°C (-40 °F). TPU has a tensile strength of 40 MPa (5.8 ksi), weaker than 56% of polymer grades. Elongation at break is 550% and the elastic modulus is 0.03 GPa (0.0044 Msi).
What is TPU used for?
- Caster and skate wheels
- Hydraulic and pneumatic seals
- Drive and timing belts
- Cable jacketing and strain reliefs
- Protective phone and device cases
- Inflatable boat fabrics
- Conveyor belt cleats and scrapers
- Footwear soles and midsoles
Advantages
- Ductile — tolerates forming and impact — 550%, better than 92% of polymer grades
- Forms and bends easily — 90/100, better than 91% of polymer grades
- Readily welded — 85/100, better than 89% of polymer grades
Limitations
- Difficult to machine — 25/100, worse than 93% of polymer grades
- Absorbs moisture — dry before molding — 0.8%, worse than 80% of polymer grades
TPU properties
Typical room-temperature values for TPU-Shore A 85; bars are the position among polymer grades.
Physical6
TPU has a density of 1.18 g/cm³ (0.0426 lb/in³), heavier than 50% of polymer grades. Its glass-transition temperature is -40°C (-40 °F).
Mechanical8
TPU has a tensile strength of 40 MPa (5.8 ksi), weaker than 56% of polymer grades. Elongation at break is 550% and the elastic modulus is 0.03 GPa (0.0044 Msi).
Thermal9
TPU is rated for continuous service to 80°C (176 °F). It conducts heat at 0.2 W/m·K (0.116 BTU/hr·ft·°F), worse than 56% of polymer grades. Thermal expansion is 170 µm/m·K (94.4 µin/in·°F).
Electrical7
TPU is an electrical insulator with a dielectric strength of 25 kV/mm (635 V/mil) and a resistivity of 1×10⁹ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (78/100), worse than 61% of polymer grades. UV resistance is fair.
Sustainability4
Producing a kilogram of TPU takes about 105 MJ of energy and emits 5.2 kg of CO₂ — more than 54% of polymer grades. Typical recycled content is 2%.
Manufacturability8
TPU's machinability is poor (25/100, worse than 93% of polymer grades); weldability excellent (85/100); formability excellent (90/100).
Common Calculations4
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the polymer family
Yield strength against density for every polymer grade FabDigit runs. TPU is highlighted; hover a dot for its name, or open the interactive family chart.
Working with TPU
Is TPU easy to machine?
Machinable but gummy — use very sharp single-flute or polished carbide tools, high speed with low feed, air blast or chilling; harder D-grades cut far better than soft A-grades.
Can TPU be welded?
Readily joined by hot-air, hot-plate, ultrasonic, RF/high-frequency and laser welding; also solvent bondable with THF/DMF and cyanoacrylate/PU adhesives.
Can TPU be formed, bent or molded?
Dry pellets 2–4 h at 80–110 °C to <0.02 % moisture, melt 195–235 °C, mould 20–50 °C, generous gates and slow-then-fast fill; extrudes and thermoforms well, shrinkage 0.5–1.8 %.
Manufacturability
The process limits FabDigit applies to TPU. Every TPU part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Poor25 / 100 |
|---|---|
| ISO material group | N.8 |
| Cutting speed (rough / finish) | 400 / 500 m/min |
| Minimum wall | 0.5 mm |
| Minimum internal radius | 1 mm |
| Drill depth limit | 10× diameter |
| Best surface (machined / polished) | Ra 0.8 / — |
| Hardenable after machining | No |
Sheet metal
| Formability | Not Recommend90 / 100 |
|---|---|
| Weldability | Not Recommend85 / 100 |
Injection molding
| Mold shrinkage | — |
|---|---|
| Wall thickness | — – — |
| Recommended draft | — |
| Pre-drying | — |
3D printing
| Technologies | SLS, FDM, MJF |
|---|---|
| Layer height | 50 – 300 µmdefault 100 µm |
| Minimum wall / feature | 1 / 0.5 mm |
| Build envelope | 300 × 300 × 380 mm |
| Supports | Yes |
| Anisotropy | Moderate |
TPU chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| MDI (4,4'-diphenylmethane diisocyanate) aromatic; HDI/H12MDI in aliphatic grades | 20 – 45 | 30 |
| 1,4-butanediol chain extender | 4 – 12 | 8 |
| processing aids / waxes / antioxidants | 0.2 – 2 | 0.8 |
| glass fiberreinforced grades only | 0 – 30 | 0 |
| flame retardant (halogen-free phosphorusFR V-0 grades only | 0 – 20 | 0 |
| polyol soft segment (polyester adipate odefines ester vs ether family | ≥ 45 (balance) |
What surface finishes work on TPU?
Takes flexible PU paints and pad/screen printing after flame or plasma pretreatment; not platable or polishable in the metal sense — surface texture is set by mould or print parameters.
Surface treatments FabDigit runs on polymer parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Coating
Injection Molding Coating
Organic Coating
Metallization / Functional
Coloring
Equivalent designations
Standards and trade names that resolve to TPU in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Trade names
- ElastollanPellethaneTexinFlexible FilamentEstaneDesmopan
- Also called
- Thermoplastic Polyurethane
How much does TPU cost?
TPU is a standard-cost polymer ($$), cheaper than about 62% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
TPU — frequently asked
What is TPU used for?
TPU is typically used for caster and skate wheels, hydraulic and pneumatic seals, drive and timing belts, cable jacketing and strain reliefs, protective phone and device cases and inflatable boat fabrics. In short: tough flexible elastic.
What is the tensile strength of TPU?
TPU has a typical tensile strength of 40 MPa (5.8 ksi) — weaker than 56% of polymer grades. Strength varies by condition: see the 19 listed tempers.
Is TPU easy to machine?
Not especially — machinability is rated poor (25/100, worse than 93% of polymer grades). Machinable but gummy — use very sharp single-flute or polished carbide tools, high speed with low feed, air blast or chilling; harder D-grades cut far better than soft A-grades.
Can TPU be welded?
Yes — weldability is rated excellent (85/100). Readily joined by hot-air, hot-plate, ultrasonic, RF/high-frequency and laser welding; also solvent bondable with THF/DMF and cyanoacrylate/PU adhesives.
What surface finishes work on TPU?
Takes flexible PU paints and pad/screen printing after flame or plasma pretreatment; not platable or polishable in the metal sense — surface texture is set by mould or print parameters.
Can TPU be formed, bent or molded?
Dry pellets 2–4 h at 80–110 °C to <0.02 % moisture, melt 195–235 °C, mould 20–50 °C, generous gates and slow-then-fast fill; extrudes and thermoforms well, shrinkage 0.5–1.8 %.
What is the maximum service temperature of TPU?
TPU is rated for continuous use to about 80°C (176 °F), and briefly to 120°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does TPU cost?
TPU is a standard-cost polymer ($$), cheaper than about 62% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in TPU?
Yes — TPU is available for CNC machining, sheet metal, injection molding and 3D printing; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- Elastollan Material Properties (TPU) brochure — BASF Polyurethanes (2023)
- Pellethane TPU product selection guide — Lubrizol Engineered Polymers (2022)
- Texin / Desmopan TPU datasheets — Covestro (2023)
- CAMPUS plastics database — TPU (ISO 10350 datasheets) — CAMPUS Consortium (2024)
- Sinterit Flexa Gray — Technical Data Sheet — Sinterit (2023)
- ISO 868 / ISO 37 / ISO 34-1 / ISO 815 elastomer test methods — ISO (2019)
- Lubrizol ESTANE 3D TPU M88A — Technical Data Sheet — Lubrizol (2023)
- Sinterit Flexa Bright — Technical Data Sheet — Sinterit (2022)
- EOS TPU 1301 — Technical Data Sheet — EOS
- Formlabs TPU 90A Powder — Technical Data Sheet — Formlabs (2023)
- Forward AM Ultrasint TPU01 — Technical Data Sheet — Forward AM (2021)
- Lubrizol ESTANE 3D TPU M95A — Technical Data Sheet — Lubrizol (2021)
- Engineered Materials Handbook Vol. 2: Engineering Plastics — ASM International (1988)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.