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PMMA-FR vs PMMA-HR

Polymer · grade comparison

PMMA-FR and PMMA-HR are both polymer grades. PMMA-HR is the stronger of the two: yield strength 72 MPa (10.4 ksi) against 62 MPa (8.99 ksi) for PMMA-FR, about 16% more; tensile strength follows at 74 MPa (10.7 ksi) vs 68 MPa (9.86 ksi). In exchange, PMMA-FR is the more ductile: elongation 4.5% versus 3.5% for PMMA-HR. PMMA-HR is stiffer (3.3 GPa vs 3.1 GPa) and PMMA-HR runs hotter in service (95°C vs 75°C continuous). On the shop floor, PMMA-FR machines more easily (very good vs good) and PMMA-HR sits in a lower cost tier (standard, $$) than PMMA-FR (premium, $$$).

PMMA-FRChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

PMMA-HRChoose it when strength drives the design, or when the part sees heat.

PMMA-FR vs PMMA-HR: properties

PMMA-FRPMMA-HR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

3.1 GPa0.45 Msi
3.3 GPa0.48 Msi

Shear Modulus

1.2 GPa0.17 Msi
1.2 GPa0.17 Msi

Bulk Modulus

5 GPa0.73 Msi
5 GPa0.77 Msi

Poisson's Ratio

0.37
0.38

Tensile Strength (Ultimate)

68 MPa9.9 ksi
74 MPa10.7 ksi

Yield Strength (0.2% offset)

62 MPa9 ksi
72 MPa10.4 ksi

Elongation at Break

4.5%
3.5%

Compressive Strength

110 MPa16 ksi
115 MPa16.7 ksi

Flexural Strength

105 MPa15.2 ksi
115 MPa16.7 ksi

Flexural Modulus

3.1 GPa0.45 Msi
3.3 GPa0.48 Msi

Shear Strength

55 MPa8 ksi
58 MPa8.4 ksi

Izod Impact, Notched

16 J/m0.3 ft·lbf/in
17 J/m0.32 ft·lbf/in

Hardness, Shore D

88 Shore D
90 Shore D

Hardness, Rockwell M

88 HRM
97 HRM

Same in both: Compressive Modulus 3 GPa0.44 Msi · Fracture Toughness (K_IC) 1.1 MPa·√m1 ksi·√in

Physical

Density and transition temperatures.

Density

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

Glass Transition (Tg)

103°C217 °F
125°C257 °F

Refractive Index

1.49
1.492

Light Transmission

89%
92%

Same in both: Water Absorption (24 h) 0.3% · Water Absorption (Saturation) 2%

Thermal

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

Thermal Expansion (CTE, 20–100 °C)

72 µm/m·K40 µin/in·°F
68 µm/m·K37.8 µin/in·°F

Max Service Temperature (continuous)

75°C167 °F
95°C203 °F

Heat Deflection Temp. @ 0.45 MPa

92°C198 °F
112°C234 °F

Heat Deflection Temp. @ 1.8 MPa

88°C190 °F
103°C217 °F

Vicat Softening Point (B50)

105°C221 °F
120°C248 °F

Limiting Oxygen Index

28%
18%

Max Service Temperature (short-term)

95°C203 °F
115°C239 °F

Same in both: Thermal Conductivity 0.19 W/m·K0.11 BTU/hr·ft·°F · Specific Heat Capacity 1,470 J/kg·K0.35 BTU/lb·°F · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Surface Resistivity

1×10¹⁵ Ω
1×10¹⁶ Ω

Same in both: Electrical Resistivity 1×10¹³ Ω·m3.94×10²⁰ µΩ·in · Dielectric Strength 25 kV/mm635 V/mil · Dielectric Constant (1 MHz) 2.8 · Dissipation Factor (1 MHz) 0.02 · Volume Resistivity 1×10¹⁵ Ω·cm · Comparative Tracking Index (CTI) 600 V

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

82 / 100
78 / 100

UV / Weathering Resistance

80 / 100
92 / 100

Manufacturability

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

Machinability

78 / 100
68 / 100

Weldability

60 / 100
55 / 100

Formability (cold)

65 / 100
60 / 100

Polishability

95 / 100
96 / 100

Mold Shrinkage

0.5%
0.45%

Melt Flow Rate

4 g/10 min
1.8 g/10 min

Processing Melt Temperature (typ.)

235°C455 °F
255°C491 °F

Mold Temperature (typ.)

70°C158 °F
85°C185 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

105 MJ/kg45,142 BTU/lb
103 MJ/kg44,282 BTU/lb

Embodied Carbon (primary production)

6.6 kg CO₂/kg
6.3 kg CO₂/kg

Embodied Water

280 L/kg33.6 gal/lb
250 L/kg30 gal/lb

Same in both: Typical Recycled Content 0%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

56 kN·m/kg
62 kN·m/kg

Specific Stiffness (E / density)

2.6 MN·m/kg
2.8 MN·m/kg

Modulus of Resilience

620 kJ/m³
785 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 scalePMMA-HRPMMA-FR

Manufacturing and finishing

CapabilityPMMA-FRPMMA-HR
Default condition——
Relative cost$$$ Premium$$ Standard
Min. machined wall——
Best machined surface——

PMMA-FR vs PMMA-HR — frequently asked

Is PMMA-HR stronger than PMMA-FR?

Yes. PMMA-HR has a typical yield strength of 72 MPa (10.4 ksi) against 62 MPa (8.99 ksi) for PMMA-FR — about 16% more. Tensile strength is 74 MPa (10.7 ksi) vs 68 MPa (9.86 ksi).

Which is cheaper, PMMA-FR or PMMA-HR?

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

Which is easier to machine, PMMA-FR or PMMA-HR?

PMMA-FR. Its machinability rates very good (78/100) against good (68/100) for PMMA-HR; for welding the order is PMMA-FR first (good, 60/100) then PMMA-HR (good, 55/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in PMMA-FR and PMMA-HR 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.