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PMMA vs PPO

Polymer · grade comparison

PMMA and PPO are both polymer grades. PMMA is the stronger of the two: yield strength 68 MPa (9.86 ksi) against 60 MPa (8.7 ksi) for PPO, about 13% more; tensile strength follows at 70 MPa (10.2 ksi) vs 60 MPa (8.7 ksi). In exchange, PPO is the more ductile: elongation 50% versus 4.5% for PMMA, and PMMA is harder (89 Shore D vs 80 Shore D). PPO is lighter (1.06 g/cm³ vs 1.19 g/cm³ for PMMA) and PMMA is stiffer (3.2 GPa vs 2.5 GPa). On the shop floor, PPO welds better (very good vs good) and PMMA sits in a lower cost tier (budget, $) than PPO (premium, $$$).

PMMAChoose it when strength drives the design, or when cost is the deciding factor.

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

PMMA vs PPO: properties

PMMAPPO

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

3.2 GPa0.46 Msi
2.5 GPa0.36 Msi

Shear Modulus

1.2 GPa0.17 Msi
0.9 GPa0.13 Msi

Bulk Modulus

6 GPa0.81 Msi
4 GPa0.51 Msi

Poisson's Ratio

0.37
0.38

Tensile Strength (Ultimate)

70 MPa10.2 ksi
60 MPa8.7 ksi

Yield Strength (0.2% offset)

68 MPa9.9 ksi
60 MPa8.7 ksi

Elongation at Break

4.5%
50%

Compressive Strength

110 MPa16 ksi
95 MPa13.8 ksi

Compressive Modulus

3.1 GPa0.45 Msi
2.4 GPa0.35 Msi

Flexural Strength

100 MPa14.5 ksi
88 MPa12.8 ksi

Flexural Modulus

3.1 GPa0.45 Msi
2.4 GPa0.35 Msi

Shear Strength

60 MPa8.7 ksi
45 MPa6.5 ksi

Fracture Toughness (K_IC)

1.2 MPa·√m1.1 ksi·√in
2.8 MPa·√m2.5 ksi·√in

Izod Impact, Notched

18 J/m0.34 ft·lbf/in
200 J/m3.7 ft·lbf/in

Hardness, Shore D

89 Shore D
80 Shore D

Hardness, Rockwell M

92 HRM
78 HRM

Hardness, Rockwell R

—
119 HRR

Physical

Density and transition temperatures.

Density

1.19 g/cm³0.04 lb/in³
1.06 g/cm³0.04 lb/in³

Glass Transition (Tg)

105°C221 °F
150°C302 °F

Water Absorption (24 h)

0.3%
0.07%

Water Absorption (Saturation)

2%
0.2%

Refractive Index

1.491
—

Light Transmission

92%
—

Thermal

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

Thermal Conductivity

0.19 W/m·K0.11 BTU/hr·ft·°F
0.22 W/m·K0.13 BTU/hr·ft·°F

Specific Heat Capacity

1,470 J/kg·K0.35 BTU/lb·°F
1,400 J/kg·K0.33 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

70 µm/m·K38.9 µin/in·°F
60 µm/m·K33.3 µin/in·°F

Max Service Temperature (continuous)

70°C158 °F
100°C212 °F

Heat Deflection Temp. @ 0.45 MPa

96°C205 °F
130°C266 °F

Heat Deflection Temp. @ 1.8 MPa

88°C190 °F
110°C230 °F

Vicat Softening Point (B50)

105°C221 °F
140°C284 °F

Limiting Oxygen Index

18%
26%

Max Service Temperature (short-term)

95°C203 °F
130°C266 °F

Same in both: Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10¹³ Ω·m3.94×10²⁰ µΩ·in
1×10¹⁴ Ω·m3.94×10²¹ µΩ·in

Dielectric Strength

25 kV/mm635 V/mil
21 kV/mm533 V/mil

Dielectric Constant (1 MHz)

2.7
2.65

Dissipation Factor (1 MHz)

0.02
9×10⁻⁴

Volume Resistivity

1×10¹⁵ Ω·cm
1×10¹⁶ Ω·cm

Comparative Tracking Index (CTI)

600 V
400 V

Same in both: Surface Resistivity 1×10¹⁵ Ω

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

UV / Weathering Resistance

92 / 100
30 / 100

Same in both: Corrosion Resistance 80 / 100

Manufacturability

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

Weldability

55 / 100
70 / 100

Formability (cold)

45 / 100
50 / 100

Polishability

96 / 100
55 / 100

Mold Shrinkage

0.5%
0.6%

Melt Flow Rate

2 g/10 min
6 g/10 min

Processing Melt Temperature (typ.)

240°C464 °F
280°C536 °F

Mold Temperature (typ.)

70°C158 °F
90°C194 °F

Same in both: Machinability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

101 MJ/kg43,422 BTU/lb
105 MJ/kg45,142 BTU/lb

Embodied Carbon (primary production)

6.4 kg CO₂/kg
4.6 kg CO₂/kg

Embodied Water

280 L/kg33.6 gal/lb
200 L/kg24 gal/lb

Typical Recycled Content

2%
5%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

59 kN·m/kg
57 kN·m/kg

Specific Stiffness (E / density)

2.7 MN·m/kg
2.4 MN·m/kg

Modulus of Resilience

723 kJ/m³
720 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 scalePMMAPPO

Manufacturing and finishing

CapabilityPMMAPPO
CNC machiningYes—
Sheet metalYes—
Injection moldingYes—
Default conditionExtruded—
Relative cost$ Budget$$$ Premium
Min. machined wall0.5 mm—
Best machined surfaceRa 0.8 µm—
Chrome Plating (Plastic)Yes—
EMI Shielding CoatingYes—
PaintingYes—
Soft Touch CoatingYes—
Spray PaintingYes—
UV CoatingYes—

PMMA vs PPO — frequently asked

Is PMMA stronger than PPO?

Yes. PMMA has a typical yield strength of 68 MPa (9.86 ksi) against 60 MPa (8.7 ksi) for PPO — about 13% more. Tensile strength is 70 MPa (10.2 ksi) vs 60 MPa (8.7 ksi).

Which is cheaper, PMMA or PPO?

PMMA is the lower-cost material: it sits in the budget tier ($) while PPO is premium ($$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which welds better, PMMA or PPO?

PPO. Its weldability rates very good (70/100) against good (55/100) for PMMA.

Ready to make it?

Upload a CAD file and FabDigit prices the part in PMMA and PPO 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.