FabDigitFabDigit

LLDPE vs UHMW-PE

Polymer · grade comparison

LLDPE and UHMW-PE are both polymer grades. UHMW-PE is the stronger of the two: yield strength 21 MPa (3.05 ksi) against 11 MPa (1.6 ksi) for LLDPE, about 91% more; tensile strength follows at 40 MPa (5.8 ksi) vs 25 MPa (3.63 ksi). In exchange, LLDPE is the more ductile: elongation 700% versus 350% for UHMW-PE, and UHMW-PE is harder (64 Shore D vs 50 Shore D). UHMW-PE is stiffer (0.72 GPa vs 0.25 GPa) and UHMW-PE conducts heat better (0.41 W/m·K vs 0.33 W/m·K). On the shop floor, UHMW-PE machines more easily (very good vs good), LLDPE welds better (excellent vs poor), and LLDPE sits in a lower cost tier (budget, $) than UHMW-PE (standard, $$).

LLDPEChoose it when the part is bent, formed or impact-loaded, or when it will be welded.

UHMW-PEChoose it when strength drives the design, or when the part is machined in volume.

LLDPE vs UHMW-PE: properties

LLDPEUHMW-PE

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

0.25 GPa0.04 Msi
0.72 GPa0.1 Msi

Shear Modulus

0.09 GPa0.01 Msi
0.25 GPa0.04 Msi

Bulk Modulus

2 GPa0.29 Msi
—

Poisson's Ratio

0.45
0.46

Tensile Strength (Ultimate)

25 MPa3.6 ksi
40 MPa5.8 ksi

Yield Strength (0.2% offset)

11 MPa1.6 ksi
21 MPa3 ksi

Elongation at Break

700%
350%

Compressive Strength

11 MPa1.6 ksi
20 MPa2.9 ksi

Compressive Modulus

0.25 GPa0.04 Msi
0.6 GPa0.09 Msi

Flexural Strength

12 MPa1.7 ksi
25 MPa3.6 ksi

Flexural Modulus

0.28 GPa0.04 Msi
0.75 GPa0.11 Msi

Shear Strength

15 MPa2.2 ksi
22 MPa3.2 ksi

Fracture Toughness (K_IC)

2.5 MPa·√m2.3 ksi·√in
3.5 MPa·√m3.2 ksi·√in

Izod Impact, Notched

800 J/m15 ft·lbf/in
1,300 J/m24.3 ft·lbf/in

Hardness, Shore A

93 Shore A
—

Hardness, Shore D

50 Shore D
64 Shore D

Hardness, Rockwell R

40 HRR
50 HRR

Physical

Density and transition temperatures.

Density

0.92 g/cm³0.03 lb/in³
0.94 g/cm³0.03 lb/in³

Melting Temperature (Tm)

123°C253 °F
135°C275 °F

Glass Transition (Tg)

-110°C-166 °F
-120°C-184 °F

Water Absorption (Saturation)

0.02%
0.01%

Same in both: Water Absorption (24 h) 0.01% · Refractive Index 1.51

Thermal

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

Thermal Conductivity

0.33 W/m·K0.19 BTU/hr·ft·°F
0.41 W/m·K0.24 BTU/hr·ft·°F

Specific Heat Capacity

2,300 J/kg·K0.55 BTU/lb·°F
1,840 J/kg·K0.44 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

180 µm/m·K100 µin/in·°F
200 µm/m·K111 µin/in·°F

Min Service Temperature

-70°C-94 °F
-200°C-328 °F

Heat Deflection Temp. @ 0.45 MPa

60°C140 °F
80°C176 °F

Heat Deflection Temp. @ 1.8 MPa

37°C99 °F
44°C111 °F

Vicat Softening Point (B50)

95°C203 °F
80°C176 °F

Limiting Oxygen Index

17%
17%

Max Service Temperature (short-term)

95°C203 °F
110°C230 °F

Same in both: Max Service Temperature (continuous) 80°C176 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10¹⁵ Ω·m3.94×10²² µΩ·in
1×10¹³ Ω·m3.94×10²⁰ µΩ·in

Dielectric Strength

25 kV/mm635 V/mil
30 kV/mm762 V/mil

Volume Resistivity

1×10¹⁷ Ω·cm
1×10¹⁵ Ω·cm

Surface Resistivity

1×10¹⁵ Ω
1×10¹⁴ Ω

Same in both: Dielectric Constant (1 MHz) 2.3 · Dissipation Factor (1 MHz) 3×10⁻⁴ · Comparative Tracking Index (CTI) 600 V

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

UV / Weathering Resistance

25 / 100
30 / 100

Same in both: Corrosion Resistance 90 / 100

Manufacturability

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

Machinability

55 / 100
75 / 100

Weldability

90 / 100
15 / 100

Formability (cold)

90 / 100
55 / 100

Polishability

30 / 100
25 / 100

Mold Shrinkage

2%
3%

Melt Flow Rate

2 g/10 min
—

Processing Melt Temperature (typ.)

210°C410 °F
200°C392 °F

Mold Temperature (typ.)

40°C104 °F
—

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

78 MJ/kg33,534 BTU/lb
85 MJ/kg36,543 BTU/lb

Embodied Carbon (primary production)

2 kg CO₂/kg
3.2 kg CO₂/kg

Embodied Water

85 L/kg10.2 gal/lb
100 L/kg12 gal/lb

Typical Recycled Content

10%
0%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

27 kN·m/kg
43 kN·m/kg

Specific Stiffness (E / density)

0.3 MN·m/kg
0.8 MN·m/kg

Modulus of Resilience

242 kJ/m³
306 kJ/m³

Same in both: Thermal Diffusivity 0.2 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 scaleUHMW-PELLDPE

Manufacturing and finishing

CapabilityLLDPEUHMW-PE
CNC machining—Yes
Sheet metal—Yes
Injection molding—Yes
Default condition—FDA
Relative cost$ Budget$$ Standard
Min. machined wall—0.5 mm
Best machined surface—Ra 0.8 µm
Chrome Plating (Plastic)—Yes
EMI Shielding Coating—Yes
Painting—Yes
Soft Touch Coating—Yes
Spray Painting—Yes
UV Coating—Yes

LLDPE vs UHMW-PE — frequently asked

Is UHMW-PE stronger than LLDPE?

Yes. UHMW-PE has a typical yield strength of 21 MPa (3.05 ksi) against 11 MPa (1.6 ksi) for LLDPE — about 91% more. Tensile strength is 40 MPa (5.8 ksi) vs 25 MPa (3.63 ksi).

Which is cheaper, LLDPE or UHMW-PE?

LLDPE is the lower-cost material: it sits in the budget tier ($) while UHMW-PE is standard ($$). 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, LLDPE or UHMW-PE?

UHMW-PE. Its machinability rates very good (75/100) against good (55/100) for LLDPE; for welding the order is LLDPE first (excellent, 90/100) then UHMW-PE (poor, 15/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in LLDPE and UHMW-PE 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.