PVC Foam (Flexible, Closed-Cell) vs Syntactic Foam (Epoxy)
Polymer · grade comparison
PVC Foam (Flexible, Closed-Cell) and Syntactic Foam (Epoxy) are both polymer grades. Syntactic Foam (Epoxy) is the stronger of the two: tensile strength 12 MPa (1.74 ksi) against 0.55 MPa (0.0798 ksi) for PVC Foam (Flexible, Closed-Cell), about 22 times as much. In exchange, PVC Foam (Flexible, Closed-Cell) is the more ductile: elongation 150% versus 1.5% for Syntactic Foam (Epoxy). PVC Foam (Flexible, Closed-Cell) is lighter (0.1 g/cm³ vs 0.45 g/cm³ for Syntactic Foam (Epoxy)) and Syntactic Foam (Epoxy) is stiffer (2.4 GPa vs 0 GPa). 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, $$) than Syntactic Foam (Epoxy) (high, $$$$).
PVC Foam (Flexible, Closed-Cell)Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
Syntactic Foam (Epoxy)Choose it when strength drives the design, or when the part sees heat.
PVC Foam (Flexible, Closed-Cell) vs Syntactic Foam (Epoxy): 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.
PVC Foam (Flexible, Closed-Cell)Syntactic Foam (Epoxy)
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Tensile Strength (Ultimate)
Elongation at Break
Compressive Strength
Compressive Modulus
Shear Strength
Hardness, Shore A
Tear Strength
Compression Set (22 h, 70 °C)
Shear Modulus
Bulk Modulus
Flexural Strength
Flexural Modulus
Fracture Toughness (K_IC)
Izod Impact, Notched
Hardness, Shore D
Hardness, Rockwell M
Same in both: Poisson's Ratio 0.3
Physical
Density and transition temperatures.
Density
Glass Transition (Tg)
Water Absorption (24 h)
Water Absorption (Saturation)
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Min Service Temperature
Limiting Oxygen Index
Max Service Temperature (short-term)
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Electrical
Conductivity and insulation.
Electrical Resistivity
Dielectric Constant (1 MHz)
Volume Resistivity
Dielectric Strength
Dissipation Factor (1 MHz)
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.)
Polishability
Mold Shrinkage
Mold Temperature (typ.)
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Thermal Diffusivity
Same in both: Thermal Shock Resistance Index 0
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 | PVC Foam (Flexible, Closed-Cell) | Syntactic Foam (Epoxy) |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$ Standard | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
PVC Foam (Flexible, Closed-Cell) vs Syntactic Foam (Epoxy) — frequently asked
Is Syntactic Foam (Epoxy) stronger than PVC Foam (Flexible, Closed-Cell)?
Yes. Syntactic Foam (Epoxy) has a typical tensile strength of 12 MPa (1.74 ksi) against 0.55 MPa (0.0798 ksi) for PVC Foam (Flexible, Closed-Cell) — about 22 times as much.
Which is cheaper, PVC Foam (Flexible, Closed-Cell) or Syntactic Foam (Epoxy)?
PVC Foam (Flexible, Closed-Cell) is the lower-cost material: it sits in the standard tier ($$) while Syntactic Foam (Epoxy) 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, PVC Foam (Flexible, Closed-Cell) or Syntactic Foam (Epoxy)?
PVC Foam (Flexible, Closed-Cell). Its machinability rates very good (78/100) against good (60/100) for Syntactic Foam (Epoxy); for welding the order is PVC Foam (Flexible, Closed-Cell) first (very good, 70/100) then Syntactic Foam (Epoxy) (not recommended, 0/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in PVC Foam (Flexible, Closed-Cell) and Syntactic Foam (Epoxy) 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.