RPET GF30 vs RPET IM
Polymer · RPET grade comparison
RPET GF30 and RPET IM are two grades of the same polymer grade, RPET: GF30 (30% glass-fibre reinforced, heat-stabilized rPET compound) versus IM (impact-modified rPET compound). The chemistry is identical, so every difference below comes from the condition. RPET GF30 is the stronger of the two: yield strength 52 MPa (7.54 ksi) against 42 MPa (6.09 ksi) for RPET IM, about 24% more; tensile strength follows at 130 MPa (18.9 ksi) vs 45 MPa (6.53 ksi). In exchange, RPET IM is the more ductile: elongation 150% versus 2.5% for RPET GF30, and RPET GF30 is harder (82 Shore D vs 75 Shore D). RPET IM is lighter (1.33 g/cm³ vs 1.57 g/cm³ for RPET GF30) and RPET GF30 is stiffer (9 GPa vs 2.1 GPa). On the shop floor, RPET IM machines more easily (good vs fair).
RPET GF30Choose it when strength drives the design, or when the part sees heat.
RPET IMChoose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
RPET GF30 vs RPET IM: 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
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Flexural Strength
Flexural Modulus
Shear Strength
Fracture Toughness (K_IC)
Izod Impact, Notched
Hardness, Shore D
Hardness, Rockwell M
Hardness, Rockwell R
Same in both: Shear Modulus 0.95 GPa0.14 Msi · Bulk Modulus 4 GPa0.58 Msi · Poisson's Ratio 0.4 · Compressive Modulus 2.5 GPa0.36 Msi
Physical
Density and transition temperatures.
Density
Same in both: Melting Temperature (Tm) 250°C482 °F · Glass Transition (Tg) 78°C172 °F · Water Absorption (24 h) 0.2% · Water Absorption (Saturation) 0.55% · Refractive Index 1.575 · Light Transmission 86%
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Vicat Softening Point (B50)
Limiting Oxygen Index
Same in both: Specific Heat Capacity 1,200 J/kg·K0.29 BTU/lb·°F · Min Service Temperature -40°C-40 °F · Max Service Temperature (short-term) 110°C230 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Resistivity 1×10¹⁴ Ω·m3.94×10²¹ µΩ·in · Dielectric Strength 20 kV/mm508 V/mil · Dielectric Constant (1 MHz) 3.2 · Dissipation Factor (1 MHz) 0.02 · Volume Resistivity 1×10¹⁶ Ω·cm · Surface Resistivity 1×10¹⁵ Ω
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: UV / Weathering Resistance 35 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Mold Shrinkage
Melt Flow Rate
Mold Temperature (typ.)
Same in both: Polishability 60 / 100 · Processing Melt Temperature (typ.) 275°C527 °F
Sustainability
Primary-production footprint per kilogram.
Typical Recycled Content
Same in both: Embodied Energy (primary production) 35 MJ/kg15,047 BTU/lb · Embodied Carbon (primary production) 1.5 kg CO₂/kg · Embodied Water 30 L/kg3.6 gal/lb
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.
RPET GF30 vs RPET IM — frequently asked
Is RPET GF30 stronger than RPET IM?
Yes. RPET GF30 has a typical yield strength of 52 MPa (7.54 ksi) against 42 MPa (6.09 ksi) for RPET IM — about 24% more. Tensile strength is 130 MPa (18.9 ksi) vs 45 MPa (6.53 ksi).
Which grade does FabDigit quote by default, GF30 or IM?
Specify the condition in the material field or the drawing note; FabDigit prices the quote for the state you call out.
Which is easier to machine, RPET GF30 or RPET IM?
RPET IM. Its machinability rates good (60/100) against fair (40/100) for RPET GF30.
Ready to make it?
Upload a CAD file and FabDigit prices the part in RPET GF30 and RPET IM 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.