RTPU
also Isoplast
High-modulus grade of thermoplastic polyurethane with rigidity approaching engineering plastics while retaining toughness and chemical resistance; used where impact resistance and stiffness are both needed.
Reference datasheet — RTPU is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
RTPU grades and fills
RTPU is supplied in 6 conditions, soft to hard.
Compare all 6 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Flame-retardant (UL 94 V-0) grade | Use for electrical enclosures, connectors and rail/transport parts needing V-0 at 1.5–3 mm; slight loss of impact and elongation. | 46 | 50 | 80 | 79 Shore D |
ESD / antistatic compounded grade | Carbon-black or permanent-antistat filled compound for tool housings and handling parts needing static dissipation. | 47 | 50 | 50 | 80 Shore D |
Hydrolysis / chemical-resistance stabilised grade | Polyether or carbodiimide-stabilised chemistry for hot-water, humid or fuel/oil-contact service (e.g. oilfield and plumbing parts). | 50 | 55 | 160 | 76 Shore D |
10 % glass-fibre reinforced | Mild stiffening step that keeps useful ductility and impact strength; good for housings needing better creep resistance. | 72 | 25 | ||
20 % glass-fibre reinforced | Balanced stiffness/toughness reinforcement for load-bearing brackets and pressurised fittings. | 95 | 8 | ||
30 % glass-fibre reinforced | Highest stiffness and strength grade; pick for metal-replacement structural parts where impact demand is moderate. | 115 | 5 |
Supply forms, finishes and certifications
Ways RTPU is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
EXT | Extruded sheet / rod stock | Supply form |
MED | Medical / USP Class VI compounded grade | Certification |
UV | UV-stabilised / weatherable grade | Grade option |
NATDefault | Unfilled / Natural | Standard supply |
What is RTPU?
High-modulus grade of thermoplastic polyurethane with rigidity approaching engineering plastics while retaining toughness and chemical resistance; used where impact resistance and stiffness are both needed. RTPU has a density of 1.2 g/cm³ (0.0434 lb/in³), heavier than 57% of polymer grades. Its glass-transition temperature is 100°C (212 °F). RTPU has a yield strength of 52 MPa (7.54 ksi) and a tensile strength of 58 MPa (8.41 ksi) — stronger than 56% of polymer grades. Elongation at break is 140% and the elastic modulus is 2.1 GPa (0.305 Msi).
What is RTPU used for?
- power tool housings
- ski boots and sporting goods
- automotive interior trim
- medical device housings
- industrial rollers
RTPU properties
Typical room-temperature values; bars are the position among polymer grades.
Physical6
RTPU has a density of 1.2 g/cm³ (0.0434 lb/in³), heavier than 57% of polymer grades. Its glass-transition temperature is 100°C (212 °F).
Mechanical13
RTPU has a yield strength of 52 MPa (7.54 ksi) and a tensile strength of 58 MPa (8.41 ksi) — stronger than 56% of polymer grades. Elongation at break is 140% and the elastic modulus is 2.1 GPa (0.305 Msi).
Thermal11
RTPU 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 85 µm/m·K (47.2 µin/in·°F).
Electrical7
RTPU is an electrical insulator with a dielectric strength of 24 kV/mm (609.6 V/mil) and a resistivity of 1×10¹² Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (80/100), worse than 52% of polymer grades. UV resistance is fair.
Sustainability4
Producing a kilogram of RTPU takes about 118 MJ of energy and emits 5.5 kg of CO₂ — more than 72% of polymer grades. Typical recycled content is 0%.
Manufacturability8
RTPU's machinability is good (55/100, worse than 64% of polymer grades); weldability very good (70/100); formability good (60/100).
Common Calculations5
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. RTPU is highlighted; hover a dot for its name, or open the interactive family chart.
Working with RTPU
Is RTPU easy to machine?
Machines like tough PC: sharp positive-rake carbide tools, high speed with low feed and air/mist cooling to avoid gumming and stress whitening; anneal stock before tight-tolerance cuts.
Can RTPU be welded?
Joins well by ultrasonic, hot-plate, spin and RF welding, and bonds with polyurethane/cyanoacrylate or solvent-type adhesives after light abrasion.
Can RTPU be formed, bent or molded?
Dry pellets 2–4 h at 90–100 °C to <0.02 % moisture, mould at 200–235 °C melt / 20–60 °C tool with generous gates; sheet thermoforms near 150–170 °C.
RTPU 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 |
|---|---|---|
| 4,4'-MDI (diphenylmethane diisocyanate hhigh hard-segment content gives rigidity | 45 – 65 | 55 |
| short-chain diol chain extender (1,4-but | 15 – 30 | 25 |
| additives (antioxidant, UV stabiliser, l | 0.2 – 2 | 0.8 |
| glass fiber0 in default unfilled grade; 10/20/30 % in GF variants | 0 – 30 | 0 |
| polyol soft segment (polyether PTMEG or polyether for hydrolysis resistance, polyester for oil/abrasion | ≥ 10 (balance) |
What surface finishes work on RTPU?
Takes paint and PU topcoats readily after adhesion promoter; can be pad-printed, laser-marked, vacuum-metallised or textured — avoid strong ketone/chlorinated solvent cleaners.
Equivalent designations
Standards and trade names that resolve to RTPU in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Trade names
- Isoplast
- Also called
- PUR-RT
How much does RTPU cost?
RTPU is a premium-cost polymer ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
RTPU — frequently asked
What is RTPU used for?
RTPU is typically used for power tool housings, ski boots and sporting goods, automotive interior trim, medical device housings and industrial rollers. In short: stiffest thermoplastic polyurethane; tough chemical-resistant housings; PC-like rigidity, higher toughness.
What is the yield strength of RTPU?
RTPU has a typical yield strength of 52 MPa (7.54 ksi) and a tensile strength of 58 MPa (8.41 ksi) — stronger than 56% of polymer grades. Strength varies by condition: see the 6 listed tempers.
Is RTPU easy to machine?
Reasonably — machinability is rated good (55/100, worse than 64% of polymer grades). Machines like tough PC: sharp positive-rake carbide tools, high speed with low feed and air/mist cooling to avoid gumming and stress whitening; anneal stock before tight-tolerance cuts.
Can RTPU be welded?
Yes — weldability is rated very good (70/100). Joins well by ultrasonic, hot-plate, spin and RF welding, and bonds with polyurethane/cyanoacrylate or solvent-type adhesives after light abrasion.
What surface finishes work on RTPU?
Takes paint and PU topcoats readily after adhesion promoter; can be pad-printed, laser-marked, vacuum-metallised or textured — avoid strong ketone/chlorinated solvent cleaners.
Can RTPU be formed, bent or molded?
Dry pellets 2–4 h at 90–100 °C to <0.02 % moisture, mould at 200–235 °C melt / 20–60 °C tool with generous gates; sheet thermoforms near 150–170 °C.
What is the maximum service temperature of RTPU?
RTPU is rated for continuous use to about 80°C (176 °F), and briefly to 110°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does RTPU cost?
RTPU is a premium-cost polymer ($$$), cheaper than about 51% 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.
Sources
- Isoplast Engineering Thermoplastic Polyurethane Resins — product and processing data — Lubrizol Engineered Polymers (2022)
- CAMPUS / UL Prospector rigid TPU (TPU-ARES/TPU-ARET) datasheets — CWFG / UL Solutions (2024)
- ASM Engineered Materials Handbook Vol. 2 — Engineering Plastics (polyurethanes) — ASM International (1988)
- ISO 527 / ISO 178 / ISO 75 / ASTM D256 test methods — ISO / ASTM (2019)
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.