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CPVC vs PVC

Polymer · grade comparison

CPVC and PVC are both polymer grades, both corrosion resistant plastic. CPVC is the stronger of the two: tensile strength 55 MPa (7.98 ksi) against 52 MPa (7.54 ksi) for PVC, about 6% more. In exchange, PVC is the more ductile: elongation 45% versus 25% for CPVC. PVC is lighter (1.42 g/cm³ vs 1.54 g/cm³ for CPVC) and CPVC runs hotter in service (93°C vs 60°C continuous). On the shop floor, PVC machines more easily (excellent vs very good), PVC welds better (excellent vs good), and PVC sits in a lower cost tier (budget, $) than CPVC (standard, $$).

CPVCChoose it when strength drives the design, or when the part sees heat.

PVCChoose it when the part is bent, formed or impact-loaded, or when weight is the constraint.

CPVC vs PVC: properties

CPVCPVC

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

55 MPa8 ksi
52 MPa7.5 ksi

Yield Strength (0.2% offset)

52 MPa7.5 ksi
50 MPa7.3 ksi

Elongation at Break

25%
45%

Compressive Strength

75 MPa10.9 ksi
68 MPa9.9 ksi

Compressive Modulus

2.7 GPa0.39 Msi
2.9 GPa0.42 Msi

Flexural Strength

95 MPa13.8 ksi
90 MPa13.1 ksi

Shear Strength

45 MPa6.5 ksi
41 MPa5.9 ksi

Izod Impact, Notched

90 J/m1.7 ft·lbf/in
55 J/m1 ft·lbf/in

Hardness, Rockwell R

118 HRR
110 HRR

Bulk Modulus

—
4 GPa0.61 Msi

Fracture Toughness (K_IC)

—
2.5 MPa·√m2.3 ksi·√in

Same in both: Elastic (Young's) Modulus 3 GPa0.44 Msi · Shear Modulus 1.1 GPa0.16 Msi · Poisson's Ratio 0.38 · Flexural Modulus 3 GPa0.44 Msi · Hardness, Shore D 82 Shore D

Physical

Density and transition temperatures.

Density

1.54 g/cm³0.06 lb/in³
1.42 g/cm³0.05 lb/in³

Glass Transition (Tg)

115°C239 °F
80°C176 °F

Water Absorption (24 h)

0.04%
0.06%

Water Absorption (Saturation)

0.25%
0.2%

Refractive Index

1.55
1.54

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

0.14 W/m·K0.08 BTU/hr·ft·°F
0.16 W/m·K0.09 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

68 µm/m·K37.8 µin/in·°F
65 µm/m·K36.1 µin/in·°F

Max Service Temperature (continuous)

93°C199 °F
60°C140 °F

Min Service Temperature

0°C32 °F
-10°C14 °F

Heat Deflection Temp. @ 0.45 MPa

118°C244 °F
75°C167 °F

Heat Deflection Temp. @ 1.8 MPa

103°C217 °F
68°C154 °F

Vicat Softening Point (B50)

115°C239 °F
80°C176 °F

Limiting Oxygen Index

60%
45%

Max Service Temperature (short-term)

105°C221 °F
80°C176 °F

Same in both: Specific Heat Capacity 950 J/kg·K0.23 BTU/lb·°F

Electrical

Conductivity and insulation.

Dielectric Constant (1 MHz)

3.4
3.1

Dissipation Factor (1 MHz)

0.014
0.015

Surface Resistivity

—
1×10¹⁴ Ω

Same in both: Electrical Resistivity 1×10¹³ Ω·m3.94×10²⁰ µΩ·in · Dielectric Strength 22 kV/mm559 V/mil · Volume Resistivity 1×10¹⁵ Ω·cm · Comparative Tracking Index (CTI) 600 V

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

85 / 100
90 / 100

Same in both: UV / Weathering Resistance 55 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

75 / 100
85 / 100

Weldability

65 / 100
90 / 100

Formability (cold)

55 / 100
80 / 100

Polishability

55 / 100
60 / 100

Mold Shrinkage

0.5%
0.4%

Processing Melt Temperature (typ.)

200°C392 °F
185°C365 °F

Mold Temperature (typ.)

55°C131 °F
40°C104 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

75 MJ/kg32,244 BTU/lb
67 MJ/kg28,805 BTU/lb

Embodied Carbon (primary production)

3 kg CO₂/kg
2.4 kg CO₂/kg

Embodied Water

180 L/kg21.6 gal/lb
120 L/kg14.4 gal/lb

Typical Recycled Content

0%
10%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

36 kN·m/kg
37 kN·m/kg

Specific Stiffness (E / density)

1.9 MN·m/kg
2.1 MN·m/kg

Modulus of Resilience

451 kJ/m³
417 kJ/m³

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.

0.1110100123Density (g/cm³)Yield strength (MPa) — log scalePVCCPVC

Manufacturing and finishing

CapabilityCPVCPVC
Default conditionUnfilledRigid (Type I)
Relative cost$$ Standard$ Budget
Min. machined wall0.5 mm0.5 mm
Best machined surfaceRa 0.8 µmRa 0.8 µm

Both are offered for CNC machining, Sheet metal and Injection molding. Both take the same 6 finishes: Chrome Plating (Plastic), EMI Shielding Coating, Painting, Soft Touch Coating, Spray Painting, UV Coating.

CPVC vs PVC — frequently asked

Is CPVC stronger than PVC?

Yes. CPVC has a typical tensile strength of 55 MPa (7.98 ksi) against 52 MPa (7.54 ksi) for PVC — about 6% more.

Which is cheaper, CPVC or PVC?

PVC is the lower-cost material: it sits in the budget tier ($) while CPVC is standard ($$). 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, CPVC or PVC?

PVC. Its machinability rates excellent (85/100) against very good (75/100) for CPVC; for welding the order is PVC first (excellent, 90/100) then CPVC (good, 65/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in CPVC and PVC 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.