PDLLA vs PLLA
Polymer · grade comparison
PDLLA and PLLA are both polymer grades. PLLA is the stronger of the two: yield strength 60 MPa (8.7 ksi) against 48 MPa (6.96 ksi) for PDLLA, about 25% more; tensile strength follows at 62 MPa (8.99 ksi) vs 50 MPa (7.25 ksi). In exchange, PDLLA is the more ductile: elongation 5% versus 4% for PLLA. PLLA is stiffer (3.5 GPa vs 3 GPa) and PLLA runs hotter in service (55°C vs 45°C continuous). On the shop floor, PLLA welds better (very good vs good) and PLLA sits in a lower cost tier (premium, $$$) than PDLLA (high, $$$$).
PDLLAChoose it when the part is bent, formed or impact-loaded.
PLLAChoose it when strength drives the design, or when the part sees heat.
PDLLA vs PLLA: 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
Compressive Modulus
Flexural Strength
Flexural Modulus
Shear Strength
Fracture Toughness (K_IC)
Izod Impact, Notched
Hardness, Shore D
Hardness, Rockwell R
Shear Modulus
Bulk Modulus
Same in both: Poisson's Ratio 0.36
Physical
Density and transition temperatures.
Density
Glass Transition (Tg)
Water Absorption (24 h)
Water Absorption (Saturation)
Light Transmission
Melting Temperature (Tm)
Same in both: Refractive Index 1.46
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
Max Service Temperature (short-term)
Same in both: Specific Heat Capacity 1,500 J/kg·K0.36 BTU/lb·°F · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Dielectric Strength
Dissipation Factor (1 MHz)
Surface Resistivity
Same in both: Electrical Resistivity 1×10¹⁴ Ω·m3.94×10²¹ µΩ·in · Dielectric Constant (1 MHz) 3 · Volume Resistivity 1×10¹⁶ Ω·cm
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
UV / Weathering Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Weldability
Formability (cold)
Mold Shrinkage
Melt Flow Rate
Processing Melt Temperature (typ.)
Same in both: Machinability 60 / 100 · Polishability 70 / 100 · Mold Temperature (typ.) 30°C86 °F
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Same in both: Typical Recycled Content 0%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
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.
Manufacturing and finishing
| Capability | PDLLA | PLLA |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$ Premium |
| Min. machined wall | — | — |
| Best machined surface | — | — |
PDLLA vs PLLA — frequently asked
Is PLLA stronger than PDLLA?
Yes. PLLA has a typical yield strength of 60 MPa (8.7 ksi) against 48 MPa (6.96 ksi) for PDLLA — about 25% more. Tensile strength is 62 MPa (8.99 ksi) vs 50 MPa (7.25 ksi).
Which is cheaper, PDLLA or PLLA?
PLLA is the lower-cost material: it sits in the premium tier ($$$) while PDLLA is high ($$$$). 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, PDLLA or PLLA?
PLLA. Its weldability rates very good (75/100) against good (55/100) for PDLLA.
Ready to make it?
Upload a CAD file and FabDigit prices the part in PDLLA and PLLA 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.