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RTPU HS

Additive grade

also Isoplast

HS = 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).

Premium cost $$$

Values for the HS condition

Other RTPU grades and fills

RTPU is listed in 6 conditions; see the grade overview at RTPU.

Compare all 6 grades and fillsHide
Grade · open for datasheetBest forYield MPaTensile MPaElong. %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.46508079 Shore D
ESD / antistatic compounded grade
Carbon-black or permanent-antistat filled compound for tool housings and handling parts needing static dissipation.47505080 Shore D
HSThis page
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).505516076 Shore D
10 % glass-fibre reinforced
Mild stiffening step that keeps useful ductility and impact strength; good for housings needing better creep resistance.—7225—
20 % glass-fibre reinforced
Balanced stiffness/toughness reinforcement for load-bearing brackets and pressurised fittings.—958—
30 % glass-fibre reinforced
Highest stiffness and strength grade; pick for metal-replacement structural parts where impact demand is moderate.—1155—

What is RTPU HS?

RTPU HS is RTPU in the HS grade — polyether or carbodiimide-stabilised chemistry for hot-water, humid or fuel/oil-contact service (e.g. oilfield and plumbing parts). RTPU HS has a yield strength of 50 MPa (7.25 ksi) and a tensile strength of 55 MPa (7.98 ksi) — stronger than 52% of polymer grades. Elongation at break is 160% and the elastic modulus is 2 GPa (0.29 Msi). RTPU HS 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 HS properties

Typical room-temperature values for RTPU HS; 26 are specific to this condition. Other listed values are RTPU reference data and may not represent this condition. Bars are the position among polymer grades.

Physical6

RTPU HS 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).

Density1.2 g/cm³0.04 lb/in³
Glass Transition (Tg)100°C212 °F
Water Absorption (24 h)0.3%
Water Absorption (Saturation)1.3%
Refractive Index1.55
Light Transmission85%

Mechanical13

RTPU HS has a yield strength of 50 MPa (7.25 ksi) and a tensile strength of 55 MPa (7.98 ksi) — stronger than 52% of polymer grades. Elongation at break is 160% and the elastic modulus is 2 GPa (0.29 Msi).

Elastic (Young's) Modulus2 GPa0.29 Msi
Poisson's Ratio0.4
Tensile Strength (Ultimate)55 MPa8 ksi
Yield Strength (0.2% offset)50 MPa7.3 ksi
Elongation at Break160%
Compressive Strength58 MPa8.4 ksi
Compressive Modulus2 GPa0.29 Msi
Flexural Strength70 MPa10.2 ksi
Flexural Modulus2 GPa0.29 Msi
Shear Strength39 MPa5.7 ksi
Izod Impact, Notched850 J/m15.9 ft·lbf/in
Hardness, Shore D76 Shore D
Hardness, Rockwell R113 HRR

Thermal11

RTPU HS is rated for continuous service to 85°C (185 °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).

Thermal Conductivity0.2 W/m·K0.12 BTU/hr·ft·°F
Specific Heat Capacity1,600 J/kg·K0.38 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)85 µm/m·K47.2 µin/in·°F
Max Service Temperature (continuous)85°C185 °F
Min Service Temperature-40°C-40 °F
Heat Deflection Temp. @ 0.45 MPa97°C207 °F
Heat Deflection Temp. @ 1.8 MPa80°C176 °F
Vicat Softening Point (B50)90°C194 °F
Flammability (UL 94)HB (unfilled, 1.5–3 mm); V-0/V-2 only with flame-retardant grades
Limiting Oxygen Index21%
Max Service Temperature (short-term)110°C230 °F

Electrical7

RTPU HS is an electrical insulator with a dielectric strength of 24 kV/mm (609.6 V/mil) and a resistivity of 1×10¹² Ω·m.

Electrical Resistivity1×10¹² Ω·m3.94×10¹⁹ µΩ·in
Dielectric Strength24 kV/mm610 V/mil
Dielectric Constant (1 MHz)4
Dissipation Factor (1 MHz)0.03
Volume Resistivity1×10¹⁴ Ω·cm
Surface Resistivity1×10¹⁴ Ω
Comparative Tracking Index (CTI)600 V

Chemical & Environmental3

Corrosion resistance is excellent (88/100), better than 74% of polymer grades. UV resistance is fair.

Corrosion ResistanceExcellent88/100
UV / Weathering ResistanceFair35/100
Chemical Resistance SummaryRetains most tensile properties after prolonged hot-water/humidity exposure and resists fuels, brine and drilling fluids better than polyester-based rigid TPU.

Sustainability4

Producing a kilogram of RTPU HS takes about 118 MJ of energy and emits 5.5 kg of CO₂ — more than 72% of polymer grades. Typical recycled content is 0%.

Embodied Energy (primary production)118 MJ/kg50,731 BTU/lb
Embodied Carbon (primary production)5.5 kg CO₂/kg
Embodied Water260 L/kg31.2 gal/lb
Typical Recycled Content0%

Manufacturability8

RTPU HS's machinability is good (60/100, better than 51% of polymer grades); weldability good (68/100); formability good (60/100).

MachinabilityGood60/100
WeldabilityGood68/100
Formability (cold)Good60/100
PolishabilityGood60/100
Mold Shrinkage0.6%
Melt Flow Rate15 g/10 min
Processing Melt Temperature (typ.)215°C419 °F
Mold Temperature (typ.)40°C104 °F

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with RTPU HS

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.

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.

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.

ElementSpec limit (wt %)Nominal
4,4'-MDI (diphenylmethane diisocyanate hhigh hard-segment content gives rigidity45 – 6555
short-chain diol chain extender (1,4-but15 – 3025
additives (antioxidant, UV stabiliser, l0.2 – 20.8
glass fiber0 in default unfilled grade; 10/20/30 % in GF variants0 – 300
polyol soft segment (polyether PTMEG or polyether for hydrolysis resistance, polyester for oil/abrasion≥ 10 (balance)—

RTPU HS — frequently asked

What is RTPU HS used for?

RTPU HS 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 HS?

RTPU HS has a typical yield strength of 50 MPa (7.25 ksi) and a tensile strength of 55 MPa (7.98 ksi) — stronger than 52% of polymer grades. Strength varies by condition: see the 6 listed tempers.

Is RTPU HS easy to machine?

Reasonably — machinability is rated good (60/100, better than 51% 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 HS be welded?

Yes — weldability is rated good (68/100). 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 HS?

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 HS 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 HS?

RTPU HS is rated for continuous use to about 85°C (185 °F), and briefly to 110°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Sources

  1. Isoplast Engineering Thermoplastic Polyurethane Resins — product and processing data — Lubrizol Engineered Polymers (2022)
  2. CAMPUS / UL Prospector rigid TPU (TPU-ARES/TPU-ARET) datasheets — CWFG / UL Solutions (2024)
  3. ASM Engineered Materials Handbook Vol. 2 — Engineering Plastics (polyurethanes) — ASM International (1988)
  4. 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. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.