PI Foam vs PVC Foam (Flexible, Closed-Cell)
Polymer · grade comparison
PI Foam and PVC Foam (Flexible, Closed-Cell) are both polymer grades. PVC Foam (Flexible, Closed-Cell) is the stronger of the two: tensile strength 0.55 MPa (0.0798 ksi) against 0.06 MPa (0.0087 ksi) for PI Foam, about 9.2 times as much. PVC Foam (Flexible, Closed-Cell) is the more ductile: elongation 150% versus 15% for PI Foam. PVC Foam (Flexible, Closed-Cell) is stiffer (0 GPa vs 3×10⁻⁴ GPa) and PI Foam runs hotter in service (300°C vs 70°C continuous). On the shop floor, PVC Foam (Flexible, Closed-Cell) machines more easily (very good vs good), PVC Foam (Flexible, Closed-Cell) welds better (very good vs not recommended), and PVC Foam (Flexible, Closed-Cell) sits in a lower cost tier (standard, $$) than PI Foam (high, $$$$).
PI FoamChoose it when the part sees heat.
PVC Foam (Flexible, Closed-Cell)Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.
PI Foam vs PVC Foam (Flexible, Closed-Cell): propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
PI FoamPVC Foam (Flexible, Closed-Cell)
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Tensile Strength (Ultimate)
Elongation at Break
Compressive Strength
Compressive Modulus
Tear Strength
Compression Set (22 h, 70 °C)
Poisson's Ratio
Shear Strength
Hardness, Shore A
Physical
Density and transition temperatures.
Glass Transition (Tg)
Density
Water Absorption (24 h)
Water Absorption (Saturation)
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Max Service Temperature (continuous)
Min Service Temperature
Limiting Oxygen Index
Max Service Temperature (short-term)
Thermal Expansion (CTE, 20–100 °C)
Electrical
Conductivity and insulation.
Electrical Resistivity
Dielectric Strength
Dielectric Constant (1 MHz)
Volume Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
UV / Weathering Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Processing Melt Temperature (typ.)
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Typical Recycled Content
Embodied Water
Strength versus weight
Yield strength against density for every polymer grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | PI Foam | PVC Foam (Flexible, Closed-Cell) |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$ Standard |
| Min. machined wall | — | — |
| Best machined surface | — | — |
PI Foam vs PVC Foam (Flexible, Closed-Cell) — frequently asked
Is PVC Foam (Flexible, Closed-Cell) stronger than PI Foam?
Yes. PVC Foam (Flexible, Closed-Cell) has a typical tensile strength of 0.55 MPa (0.0798 ksi) against 0.06 MPa (0.0087 ksi) for PI Foam — about 9.2 times as much.
Which is cheaper, PI Foam or PVC Foam (Flexible, Closed-Cell)?
PVC Foam (Flexible, Closed-Cell) is the lower-cost material: it sits in the standard tier ($$) while PI Foam is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which is easier to machine, PI Foam or PVC Foam (Flexible, Closed-Cell)?
PVC Foam (Flexible, Closed-Cell). Its machinability rates very good (78/100) against good (55/100) for PI Foam; for welding the order is PVC Foam (Flexible, Closed-Cell) first (very good, 70/100) then PI Foam (not recommended, 5/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in PI Foam and PVC Foam (Flexible, Closed-Cell) side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.