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PMMA-GP vs PMMA-HI

Polymer · grade comparison

PMMA-GP and PMMA-HI are both polymer grades. PMMA-GP is the stronger of the two: yield strength 70 MPa (10.2 ksi) against 48 MPa (6.96 ksi) for PMMA-HI, about 46% more; tensile strength follows at 72 MPa (10.4 ksi) vs 50 MPa (7.25 ksi). In exchange, PMMA-HI is the more ductile: elongation 30% versus 4.5% for PMMA-GP. PMMA-GP is stiffer (3.2 GPa vs 2.2 GPa).

PMMA-GPChoose it when strength drives the design.

PMMA-HIChoose it when the part is bent, formed or impact-loaded.

PMMA-GP vs PMMA-HI: properties

PMMA-GPPMMA-HI

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

3.2 GPa0.46 Msi
2.2 GPa0.32 Msi

Shear Modulus

1.2 GPa0.17 Msi
0.85 GPa0.12 Msi

Bulk Modulus

5 GPa0.73 Msi
5 GPa0.65 Msi

Tensile Strength (Ultimate)

72 MPa10.4 ksi
50 MPa7.3 ksi

Yield Strength (0.2% offset)

70 MPa10.2 ksi
48 MPa7 ksi

Elongation at Break

4.5%
30%

Compressive Strength

110 MPa16 ksi
88 MPa12.8 ksi

Compressive Modulus

3.1 GPa0.45 Msi
2.3 GPa0.33 Msi

Flexural Strength

105 MPa15.2 ksi
78 MPa11.3 ksi

Flexural Modulus

3.2 GPa0.46 Msi
2.3 GPa0.33 Msi

Shear Strength

60 MPa8.7 ksi
45 MPa6.5 ksi

Fracture Toughness (K_IC)

1.2 MPa·√m1.1 ksi·√in
2.2 MPa·√m2 ksi·√in

Izod Impact, Notched

18 J/m0.34 ft·lbf/in
70 J/m1.3 ft·lbf/in

Hardness, Shore D

90 Shore D
86 Shore D

Hardness, Rockwell M

95 HRM
60 HRM

Hardness, Rockwell R

125 HRR
112 HRR

Same in both: Poisson's Ratio 0.38

Physical

Density and transition temperatures.

Density

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

Glass Transition (Tg)

105°C221 °F
102°C216 °F

Water Absorption (Saturation)

2%
1.9%

Refractive Index

1.491
1.49

Light Transmission

92%
89%

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

Thermal

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

Thermal Expansion (CTE, 20–100 °C)

70 µm/m·K38.9 µin/in·°F
75 µm/m·K41.7 µin/in·°F

Max Service Temperature (continuous)

75°C167 °F
72°C162 °F

Heat Deflection Temp. @ 0.45 MPa

98°C208 °F
88°C190 °F

Heat Deflection Temp. @ 1.8 MPa

92°C198 °F
80°C176 °F

Vicat Softening Point (B50)

108°C226 °F
100°C212 °F

Limiting Oxygen Index

18%
18%

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 · Max Service Temperature (short-term) 90°C194 °F

Electrical

Conductivity and insulation.

Dielectric Constant (1 MHz)

2.7
2.8

Dissipation Factor (1 MHz)

0.02
0.022

Surface Resistivity

1×10¹⁶ Ω
1×10¹⁵ Ω

Same in both: Electrical Resistivity 1×10¹³ Ω·m3.94×10²⁰ µΩ·in · Dielectric Strength 25 kV/mm635 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

80 / 100
75 / 100

UV / Weathering Resistance

95 / 100
82 / 100

Manufacturability

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

Machinability

75 / 100
78 / 100

Weldability

65 / 100
62 / 100

Formability (cold)

70 / 100
82 / 100

Polishability

98 / 100
85 / 100

Mold Shrinkage

0.5%
0.55%

Melt Flow Rate

3 g/10 min
4 g/10 min

Processing Melt Temperature (typ.)

240°C464 °F
235°C455 °F

Same in both: Mold Temperature (typ.) 70°C158 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

100 MJ/kg42,992 BTU/lb
103 MJ/kg44,282 BTU/lb

Embodied Carbon (primary production)

6 kg CO₂/kg
5.6 kg CO₂/kg

Embodied Water

250 L/kg30 gal/lb
300 L/kg35.9 gal/lb

Typical Recycled Content

0%
2%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

61 kN·m/kg
43 kN·m/kg

Specific Stiffness (E / density)

2.7 MN·m/kg
1.9 MN·m/kg

Modulus of Resilience

766 kJ/m³
524 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-GPPMMA-HI

Manufacturing and finishing

CapabilityPMMA-GPPMMA-HI
Default condition——
Relative cost$$ Standard$$ Standard
Min. machined wall——
Best machined surface——

PMMA-GP vs PMMA-HI — frequently asked

Is PMMA-GP stronger than PMMA-HI?

Yes. PMMA-GP has a typical yield strength of 70 MPa (10.2 ksi) against 48 MPa (6.96 ksi) for PMMA-HI — about 46% more. Tensile strength is 72 MPa (10.4 ksi) vs 50 MPa (7.25 ksi).

Which is cheaper, PMMA-GP or PMMA-HI?

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.

When should I choose PMMA-GP over PMMA-HI?

Pick PMMA-GP when strength drives the design. Pick PMMA-HI when the part is bent, formed or impact-loaded.

Ready to make it?

Upload a CAD file and FabDigit prices the part in PMMA-GP and PMMA-HI 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.