Poron
also Microcellular Urethane
Poron is a microcellular cast polyurethane foam (AU/EU cast PU family) supplied as skived sheet and roll in VerySoft, Standard, Firm and ExtraFirm densities plus FR, AquaPro, XRD and MED variants.
Poron grades and fills
Poron 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 |
|---|---|---|---|---|---|
ultra-low CFD grades (e.g. PORON 4790-92-15/-20, EVExtend very soft) | Use where closure force must be minimal — thin-wall plastic housings, OLED module cushions, low-force dust seals. | 0.6 | 180 | 10 Shore A | |
High strain-rate impact-protection urethane | Rate-sensitive grade that stiffens on impact — used in protective sports/PPE padding and drop protection rather than static gasketing. | 0.9 | 180 | 15 Shore A | |
Flame-retardant grades | Required for battery packs, power supplies and automotive interiors needing a V-0 or FMVSS 302 rated cushion. | 1 | 140 | 22 Shore A | |
Sealing grade for IP-rated water/dust resistance | Choose for IPX4–IPX7 style gaskets in phones and wearables where thin, low-force water sealing is needed. | 1 | 150 | 25 Shore A | |
Higher-density/firmer microcellular urethane | Pick when the pad must carry higher load or resist thinning under sustained clamp force, e.g. structural standoff and vibration pads. | 2 | 140 | 28 Shore A | |
highest-density load-bearing grades (e.g. PORON 4701-50, HP firm) | For load spreading, bumpers and vibration isolation pads where deflection must stay small under continuous load. | 2 | 120 | 35 Shore A |
Supply forms, finishes and certifications
Ways Poron is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
MED | Medical / skin-contact grade | Certification |
StandardDefault | Soft/very soft microcellular urethane | Standard supply |
What is Poron?
Poron is a microcellular cast polyurethane foam (AU/EU cast PU family) supplied as skived sheet and roll in VerySoft, Standard, Firm and ExtraFirm densities plus FR, AquaPro, XRD and MED variants. Engineers specify it for low compression set and repeatable cushioning in thin gaskets and pads, with nominal density 0.32 g/cm3, tensile strength 1 MPa, elongation 170 % and service to 90 °C. It carries no structural load and is not weldable, and it costs more than closed-cell EVA or PE foam, which remain the cheaper choice when long-term recovery is not required. Poron has a density of 0.32 g/cm³ (0.0116 lb/in³), lighter than 85% of polymer grades. Its glass-transition temperature is -35°C (-31 °F). Poron has a tensile strength of 1 MPa (0.145 ksi), weaker than 86% of polymer grades. Elongation at break is 150% and the elastic modulus is 0 GPa (2.18×10⁻⁴ Msi).
What is Poron used for?
- Electronic enclosure sealing gaskets
- Vibration and shock dampers
- Display and touchscreen cushions
- Wearable device skin-contact padding
- Impact padding in protective gear
- Battery pack compression pads
- Keypad and button cushions
- Weather-resistant housing seals
Advantages
- Forms and bends easily — 90/100, better than 91% of polymer grades
- Lightweight — 0.32 g/cm³ (0.0116 lb/in³), better than 85% of polymer grades
- Easy to machine — 80/100, better than 84% of polymer grades
Limitations
- Absorbs moisture — dry before molding — 3%, worse than 99% of polymer grades
- Low stiffness — 0 GPa (2.18×10⁻⁴ Msi), worse than 96% of polymer grades
- Poor heat conductor — 0.06 W/m·K (0.0347 BTU/hr·ft·°F), worse than 84% of polymer grades
- Needs corrosion protection — 70/100, worse than 78% of polymer grades
Poron properties
Typical room-temperature values in the Standard condition; bars are the position among polymer grades.
Physical3
Poron has a density of 0.32 g/cm³ (0.0116 lb/in³), lighter than 85% of polymer grades. Its glass-transition temperature is -35°C (-31 °F).
Mechanical9
Poron has a tensile strength of 1 MPa (0.145 ksi), weaker than 86% of polymer grades. Elongation at break is 150% and the elastic modulus is 0 GPa (2.18×10⁻⁴ Msi).
Thermal6
Poron is rated for continuous service to 90°C (194 °F). It conducts heat at 0.06 W/m·K (0.0347 BTU/hr·ft·°F), worse than 84% of polymer grades.
Electrical2
Chemical & Environmental3
Corrosion resistance is very good (70/100), worse than 78% of polymer grades. UV resistance is fair.
Sustainability3
Producing a kilogram of Poron takes about 100 MJ of energy and emits 5 kg of CO₂ — less than 61% of polymer grades. Typical recycled content is 0%.
Manufacturability2
Poron's machinability is very good (80/100, better than 84% of polymer grades); formability excellent (90/100).
Common Calculations3
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. Poron is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Poron
Is Poron easy to machine?
Convert by steel-rule die, rotary kiss-cut, laser (with fume extraction) or waterjet; avoid conventional milling — the foam tears and compresses under tool load.
Can Poron be welded?
Not weldable; join with acrylic PSA transfer tape, urethane adhesive or mechanical capture in a housing groove.
Can Poron be formed, bent or molded?
Supplied as cast/skived sheet and roll; forms only by compression in the assembly — design for 20–50 % working deflection and avoid >70 % compression to preserve recovery.
Manufacturability
The process limits FabDigit applies to Poron. Every Poron part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
Injection molding
| Mold shrinkage | — |
|---|---|
| Wall thickness | — – — |
| Recommended draft | — |
| Pre-drying | — |
Poron 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 |
|---|---|---|
| polyester/polyether polyolsoft-segment backbone; ether-type used for hydrolysis-resistant grades | 50 – 70 | 60 |
| diisocyanate (MDI/TDI)hard-segment / crosslinker | 20 – 40 | 30 |
| cell-control additives, surfactants, pigmicrocellular structure control | 2 – 10 | 5 |
| flame retardant (FR grades only)present only in UL 94 V-0 variants | 0 – 15 | 8 |
What surface finishes work on Poron?
No coating needed; surfaces are as-skived or film/PSA laminated, and can be printed or laminated with PET/PI films for low-friction or shielding layers.
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).
Injection Molding Coating
Metallization / Functional
Equivalent designations
Standards and trade names that resolve to Poron in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Trade names
- Microcellular Urethane
How much does Poron cost?
Poron is a standard-cost polymer ($$), cheaper than about 62% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Poron — frequently asked
What is Poron used for?
Poron is typically used for electronic enclosure sealing gaskets, vibration and shock dampers, display and touchscreen cushions, wearable device skin-contact padding, impact padding in protective gear and battery pack compression pads. In short: cushioning microcellular urethane.
What is the tensile strength of Poron?
Poron has a typical tensile strength of 1 MPa (0.145 ksi) — weaker than 86% of polymer grades. Strength varies by condition: see the 6 listed tempers.
Is Poron easy to machine?
Yes — machinability is rated very good (80/100, better than 84% of polymer grades). Convert by steel-rule die, rotary kiss-cut, laser (with fume extraction) or waterjet; avoid conventional milling — the foam tears and compresses under tool load.
Can Poron be welded?
Not weldable; join with acrylic PSA transfer tape, urethane adhesive or mechanical capture in a housing groove.
What surface finishes work on Poron?
No coating needed; surfaces are as-skived or film/PSA laminated, and can be printed or laminated with PET/PI films for low-friction or shielding layers.
Can Poron be formed, bent or molded?
Supplied as cast/skived sheet and roll; forms only by compression in the assembly — design for 20–50 % working deflection and avoid >70 % compression to preserve recovery.
What is the maximum service temperature of Poron?
Poron is rated for continuous use to about 90°C (194 °F), and briefly to 120°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Poron cost?
Poron is a standard-cost polymer ($$), 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 Poron?
Yes — Poron is available for injection molding; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- PORON Microcellular Urethane Product Data (4701 / 4790 series, AquaPro, XRD) — Rogers Corporation (2023)
- ASTM D1056 — Flexible Cellular Materials, Sponge or Expanded Rubber — ASTM (2020)
- ASTM D3574 — Flexible Cellular Materials, Slab, Bonded and Molded Urethane Foams — ASTM (2017)
- UL 94 — Tests for Flammability of Plastic Materials — UL (2020)
- Polyurethane Handbook (structure–property data for microcellular elastomers) — Hanser (1994)
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.