CPVC 4120 vs PVC-O
Polymer · grade comparison
CPVC 4120 and PVC-O are both polymer grades. PVC-O is the stronger of the two: yield strength 58 MPa (8.41 ksi) against 52 MPa (7.54 ksi) for CPVC 4120, about 12% more; tensile strength follows at 78 MPa (11.3 ksi) vs 55 MPa (7.98 ksi). PVC-O is the more ductile: elongation 90% versus 25% for CPVC 4120. PVC-O is lighter (1.4 g/cm³ vs 1.53 g/cm³ for CPVC 4120) and PVC-O is stiffer (3.8 GPa vs 3 GPa). On the shop floor, CPVC 4120 machines more easily (80 vs 70 out of 100) and CPVC 4120 welds better (very good vs poor).
CPVC 4120Choose it when the part sees heat, or when the part is machined in volume.
PVC-OChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
CPVC 4120 vs PVC-O: 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.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Shear Modulus
Bulk Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Modulus
Flexural Strength
Flexural Modulus
Shear Strength
Fracture Toughness (K_IC)
Izod Impact, Notched
Hardness, Rockwell R
Same in both: Poisson's Ratio 0.38 · Compressive Strength 65 MPa9.4 ksi · Hardness, Shore D 82 Shore D
Physical
Density and transition temperatures.
Density
Glass Transition (Tg)
Water Absorption (Saturation)
Refractive Index
Same in both: Water Absorption (24 h) 0.04%
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Min Service Temperature
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Vicat Softening Point (B50)
Limiting Oxygen Index
Max Service Temperature (short-term)
Same in both: Specific Heat Capacity 950 J/kg·K0.23 BTU/lb·°F
Electrical
Conductivity and insulation.
Dielectric Strength
Dielectric Constant (1 MHz)
Dissipation Factor (1 MHz)
Surface Resistivity
Comparative Tracking Index (CTI)
Same in both: Electrical Resistivity 1×10¹³ Ω·m3.94×10²⁰ µΩ·in · Volume Resistivity 1×10¹⁵ Ω·cm
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
UV / Weathering Resistance
Same in both: Corrosion Resistance 92 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Polishability
Mold Shrinkage
Processing Melt Temperature (typ.)
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)
Modulus of Resilience
Same in both: Thermal Diffusivity 0.1 mm²/s · 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 | CPVC 4120 | PVC-O |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$ Standard | $$ Standard |
| Min. machined wall | — | — |
| Best machined surface | — | — |
CPVC 4120 vs PVC-O — frequently asked
Is PVC-O stronger than CPVC 4120?
Yes. PVC-O has a typical yield strength of 58 MPa (8.41 ksi) against 52 MPa (7.54 ksi) for CPVC 4120 — about 12% more. Tensile strength is 78 MPa (11.3 ksi) vs 55 MPa (7.98 ksi).
Which is cheaper, CPVC 4120 or PVC-O?
Both sit in the same relative cost tier ($$, standard); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, CPVC 4120 or PVC-O?
CPVC 4120, by a small margin. Both rate very good for machinability — 80/100 against 70/100 for PVC-O; for welding the order is CPVC 4120 first (very good, 70/100) then PVC-O (poor, 25/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in CPVC 4120 and PVC-O 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.