PES
ASTM D5205 · also Ultrason E
PES (polyethersulfone) is a transparent amorphous sulfone thermoplastic covered by ASTM D5205 and sold as Ultrason E, with a glass transition near 225 °C, 84 MPa tensile strength, 2.6 GPa modulus, 50 % elongation and a density of 1.37 g/cm³.
Reference datasheet — PES 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.
PES grades and fills
PES is supplied in 8 conditions, soft to hard.
Compare all 8 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Bearing / lubricated grade | Use for high-temperature dry-running bushings, thrust washers and slide elements. | 70 | 70 | 12 | 84 Shore D |
ESD / conductive compound | Choose for wafer-handling, cleanroom and electronics fixtures needing controlled surface resistivity at high temperature. | 75 | 75 | 8 | 87 Shore D |
Membrane grade | Solution-grade high-molecular-weight PES powder dissolved in NMP/DMAc to cast UF, MF, dialysis and RO support membranes. | 85 | 85 | 60 | 86 Shore D |
10 % glass-fibre reinforced | Light reinforcement when moderate stiffness gain is needed with less warpage than GF30. | 105 | 5 | ||
20 % glass-fibre reinforced | Balanced stiffness/toughness grade for structural housings and hot-water manifolds. | 125 | 3.5 | 92 HRM | |
30 % glass-fibre reinforced | Highest-stiffness standard grade for load-bearing high-temperature parts and metal replacement. | 140 | 2.7 | 95 HRM | |
40 % glass-fibre reinforced | Maximum stiffness and minimum CTE for precision high-temperature structural mouldings. | 155 | 2.2 | ||
30 % carbon-fibre reinforced | Pick when maximum specific stiffness, low CTE and static-dissipative behaviour are required. | 175 | 1.6 |
Supply forms, finishes and certifications
Ways PES is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
EXTR | Extrusion / stock-shape grade | Surface finish |
MED | Medical / food-contact grade | Certification |
UnfilledDefault | Unfilled / Natural | Standard supply |
What is PES?
PES (polyethersulfone) is a transparent amorphous sulfone thermoplastic covered by ASTM D5205 and sold as Ultrason E, with a glass transition near 225 °C, 84 MPa tensile strength, 2.6 GPa modulus, 50 % elongation and a density of 1.37 g/cm³. Engineers pick it for repeated steam sterilization, hydrolysis and radiation resistance, in unfilled, 10–40 % glass, 30 % carbon, lubricated, ESD, medical, membrane and extrusion grades. It is stress-crack sensitive in ketones and chlorinated fluids, must be dried before moulding, yellows under UV and costs more than PSU. PES has a density of 1.37 g/cm³ (0.0495 lb/in³), heavier than 76% of polymer grades. Its glass-transition temperature is 225°C (437 °F). PES has a yield strength of 84 MPa (12.2 ksi) and a tensile strength of 84 MPa (12.2 ksi) — stronger than 89% of polymer grades. Elongation at break is 50% and the elastic modulus is 2.6 GPa (0.377 Msi).
What is PES used for?
- dialysis and filtration membranes
- medical device housings
- aircraft cabin parts
- electrical insulators
Advantages
- High strength — 84 MPa (12.2 ksi), better than 89% of polymer grades
- High service temperature — 180°C (356 °F), better than 85% of polymer grades
- Polishes to a fine finish — 70/100, better than 77% of polymer grades
Limitations
- High embodied carbon — 8 kg CO₂/kg, worse than 83% of polymer grades
- Heavy — 1.37 g/cm³ (0.0495 lb/in³), worse than 76% of polymer grades
- Degrades in UV without stabilisers — 25/100, worse than 76% of polymer grades
PES properties
Typical room-temperature values; bars are the position among polymer grades.
Physical6
PES has a density of 1.37 g/cm³ (0.0495 lb/in³), heavier than 76% of polymer grades. Its glass-transition temperature is 225°C (437 °F).
Mechanical17
PES has a yield strength of 84 MPa (12.2 ksi) and a tensile strength of 84 MPa (12.2 ksi) — stronger than 89% of polymer grades. Elongation at break is 50% and the elastic modulus is 2.6 GPa (0.377 Msi).
Thermal11
PES is rated for continuous service to 180°C (356 °F). It conducts heat at 0.18 W/m·K (0.104 BTU/hr·ft·°F), worse than 73% of polymer grades. Thermal expansion is 55 µm/m·K (30.6 µin/in·°F).
Electrical7
PES is an electrical insulator with a dielectric strength of 16 kV/mm (406.4 V/mil) and a resistivity of 1×10¹⁴ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (80/100), worse than 52% of polymer grades. UV resistance is poor.
Sustainability4
Producing a kilogram of PES takes about 145 MJ of energy and emits 8 kg of CO₂ — more than 83% of polymer grades. Typical recycled content is 0%.
Manufacturability8
PES's machinability is good (65/100, better than 66% of polymer grades); weldability very good (70/100); formability good (55/100).
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. PES is highlighted; hover a dot for its name, or open the interactive family chart.
Working with PES
Is PES easy to machine?
Machines cleanly with sharp carbide, high speed and light feeds; use air or water-soluble coolant only (avoid chlorinated/ketone fluids) and anneal at ~190 °C before and after heavy cuts to prevent stress cracking.
Can PES be welded?
Joins well by ultrasonic, hot-plate, IR and vibration welding, plus solvent bonding with NMP/DMAc-based cements; glass-filled grades give lower weld-line strength.
Can PES be formed, bent or molded?
Dry to <0.02 % moisture (150 °C, 3–4 h), mould at 340–380 °C melt with 140–180 °C tools, generous gates and slow injection; thermoforming of sheet at 240–280 °C is practical.
PES 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 |
|---|---|---|
| glass fiber0 in default grade; 10–40 % in GF variants | 0 – 40 | 0 |
| carbon fiberCF and ESD variants only | 0 – 30 | 0 |
| PTFE / graphite lubricantbearing grades only | 0 – 20 | 0 |
| poly(oxy-1,4-phenylenesulfonyl-1,4-phenyAmorphous polyarylethersulfone, typically from bisphenol S / 4,4'-dichlorodiphenyl sulfone polycondensation; unfilled grade | balance |
What surface finishes work on PES?
Accepts printing, painting and vacuum metallising after plasma or primer treatment; unstabilised parts yellow under UV, so use topcoats or UV-shielding paint for outdoor service.
Equivalent designations
Standards and trade names that resolve to PES in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- D5205
- Trade names
- Ultrason E
How much does PES cost?
PES is a high-cost polymer ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
PES — frequently asked
What is PES used for?
PES is typically used for dialysis and filtration membranes, medical device housings, aircraft cabin parts and electrical insulators. In short: high-Tg transparent sulfone; steam- and radiation-resistant; membrane-casting resin.
What is the yield strength of PES?
PES has a typical yield strength of 84 MPa (12.2 ksi) and a tensile strength of 84 MPa (12.2 ksi) — stronger than 89% of polymer grades. Strength varies by condition: see the 8 listed tempers.
Is PES easy to machine?
Reasonably — machinability is rated good (65/100, better than 66% of polymer grades). Machines cleanly with sharp carbide, high speed and light feeds; use air or water-soluble coolant only (avoid chlorinated/ketone fluids) and anneal at ~190 °C before and after heavy cuts to prevent stress cracking.
Can PES be welded?
Yes — weldability is rated very good (70/100). Joins well by ultrasonic, hot-plate, IR and vibration welding, plus solvent bonding with NMP/DMAc-based cements; glass-filled grades give lower weld-line strength.
What surface finishes work on PES?
Accepts printing, painting and vacuum metallising after plasma or primer treatment; unstabilised parts yellow under UV, so use topcoats or UV-shielding paint for outdoor service.
Can PES be formed, bent or molded?
Dry to <0.02 % moisture (150 °C, 3–4 h), mould at 340–380 °C melt with 140–180 °C tools, generous gates and slow injection; thermoforming of sheet at 240–280 °C is practical.
What is the maximum service temperature of PES?
PES is rated for continuous use to about 180°C (356 °F), and briefly to 220°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does PES cost?
PES is a high-cost polymer ($$$$), pricier than about 78% 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
- Ultrason E (PES) product brochure and processing guide — BASF (2023)
- Veradel PESU / Radel resins design guide — Solvay Specialty Polymers (2022)
- Sumikaexcel PES technical data — Sumitomo Chemical (2021)
- TECASON E (PESU) stock shape datasheet — Ensinger (2023)
- CAMPUS plastics database, PESU entries (ISO 10350 sets) — CWFG / CAMPUS consortium (2024)
- Engineered Materials Handbook Vol. 2: Engineering Plastics — ASM International (1988)
- ISO 527 / ISO 75 / ISO 306 / UL 94 test methods — ISO / UL (2020)
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.