LLDPE XL
Grade
ASTM D1248 Type I · ISO PE-LLD
XL = crosslinkable / peroxide-crosslinked LLDPE
Choose for fuel tanks, chemical tanks and wire insulation where peroxide crosslinking raises heat resistance to 105 °C plus ESCR and hydrocarbon resistance, but the part can no longer be remelted or recycled.
Values for the XL condition
Other LLDPE grades and fills
LLDPE is listed in 6 conditions; see the grade overview at LLDPE.
Compare all 6 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Metallocene LLDPE | Choose the narrow-MWD metallocene C6/C8 resin for films and seal layers needing higher clarity, heat sealability and puncture/tear strength, reaching 45 MPa tensile and 800 % elongation. | 10 | 45 | 800 | 46 Shore D |
Injection-moulding grade | Choose the high-MFI 15–50 injection grade for thin-wall closures, containers and toys where fast filling and short cycles rule; tensile 18 MPa and ESCR sit below the film grades. | 11 | 18 | 500 | 52 Shore D |
Flame-retardant | Pick for low-smoke halogen-free cable sheathing and building products: about 60 % ATH/MDH mineral loading buys V-0 and LOI ≥ 30 but cuts elongation to 180 % and hurts flexibility and processing. | 11 | 12 | 180 | 58 Shore D |
Carbon-black (2–2.5 %) weatherable black compound | Pick the 2–2.5 % carbon-black compound for mulch film, geomembranes, pipe and cable jacketing where the best long-term outdoor weathering matters; the part is opaque black, elongation 650 %. | 12 | 26 | 650 | 52 Shore D |
XLThis page Crosslinkable / peroxide-crosslinked LLDPE | Choose for fuel tanks, chemical tanks and wire insulation where peroxide crosslinking raises heat resistance to 105 °C plus ESCR and hydrocarbon resistance, but the part can no longer be remelted or recycled. | 14 | 20 | 400 | 58 Shore D |
Rotomoulding grade | Use the hexene rotomoulding grade at ~0.935 g/cm³ and MFI 3–6 for water tanks, chemical tanks and road barriers; powder flow and sintering are good with excellent low-temperature impact. | 17 | 22 | 600 | 58 Shore D |
What is LLDPE XL?
LLDPE XL is LLDPE in the XL grade — choose for fuel tanks, chemical tanks and wire insulation where peroxide crosslinking raises heat resistance to 105 °C plus ESCR and hydrocarbon resistance, but the part can no longer be remelted or recycled. LLDPE XL has a yield strength of 14 MPa (2.03 ksi) and a tensile strength of 20 MPa (2.9 ksi) — weaker than 84% of polymer grades. Elongation at break is 400% and the elastic modulus is 0.55 GPa (0.0798 Msi). LLDPE XL has a density of 0.92 g/cm³ (0.0332 lb/in³), lighter than 80% of polymer grades. Its glass-transition temperature is -110°C (-166 °F).
Advantages
- Low moisture uptake — 0.01%, better than 97% of polymer grades
- Low embodied carbon — 2 kg CO₂/kg, better than 96% of polymer grades
- Conducts heat well — 0.35 W/m·K (0.202 BTU/hr·ft·°F), better than 91% of polymer grades
- Ductile — tolerates forming and impact — 400%, better than 86% of polymer grades
- Good corrosion resistance — 90/100, better than 82% of polymer grades
Limitations
- High mold shrinkage — 3%, worse than 97% of polymer grades
- Low strength — 14 MPa (2.03 ksi), worse than 84% of polymer grades
- Difficult to weld — 10/100, worse than 82% of polymer grades
- Hard to polish — 30/100, worse than 82% of polymer grades
- Difficult to machine — 45/100, worse than 78% of polymer grades
LLDPE XL properties
Typical room-temperature values for LLDPE XL; 30 are specific to this condition. Other listed values are LLDPE reference data and may not represent this condition. Bars are the position among polymer grades.
Physical6
LLDPE XL has a density of 0.92 g/cm³ (0.0332 lb/in³), lighter than 80% of polymer grades. Its glass-transition temperature is -110°C (-166 °F).
Mechanical17
LLDPE XL has a yield strength of 14 MPa (2.03 ksi) and a tensile strength of 20 MPa (2.9 ksi) — weaker than 84% of polymer grades. Elongation at break is 400% and the elastic modulus is 0.55 GPa (0.0798 Msi).
Thermal11
LLDPE XL is rated for continuous service to 105°C (221 °F). It conducts heat at 0.35 W/m·K (0.202 BTU/hr·ft·°F), better than 91% of polymer grades. Thermal expansion is 180 µm/m·K (100 µin/in·°F).
Electrical7
LLDPE XL is an electrical insulator with a dielectric strength of 25 kV/mm (635 V/mil) and a resistivity of 1×10¹⁵ Ω·m.
Chemical & Environmental3
Corrosion resistance is excellent (90/100), better than 82% of polymer grades. UV resistance is poor.
Sustainability4
Producing a kilogram of LLDPE XL takes about 78 MJ of energy and emits 2 kg of CO₂ — less than 88% of polymer grades. Typical recycled content is 10%.
Manufacturability8
LLDPE XL's machinability is fair (45/100, worse than 78% of polymer grades); weldability not recommended (10/100); formability poor (30/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with LLDPE XL
Is LLDPE easy to machine?
Turns, mills and drills, but the material is soft and gummy: use sharp large positive-rake tools, high spindle speed, generous feed and air cooling to clear chips and avoid heat distortion. Dimensions drift with temperature and internal stress, so it is unsuitable for tight-tolerance machined parts.
Can LLDPE be welded?
Heat fusion is excellent — hot-plate, hot-gas rod, extrusion welding, heat sealing and ultrasonic or RF welding (RF needs polar additives) all work. Only crosslinked XL grades cannot be re-welded.
Can LLDPE be formed, bent or molded?
Processed mainly by blown or cast film, injection moulding, rotomoulding and extrusion. Melt strength is lower than LDPE, so blown film needs higher back pressure and air-ring adjustment; shrinkage is 1.5–3%, and rotomoulded wall thickness should be compensated for about 3% shrink.
What surface finishes work on LLDPE?
The non-polar surface must be corona-, flame- or plasma-treated to at least 38 dyn/cm before printing, coating or adhesive bonding. Plating is not possible; colour with masterbatch rather than paint.
LLDPE chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| 1-butene / 1-hexene / 1-octene comonomerα-olefin giving short-chain branching; C6/C8 give better tear & ESCR than C4 | 1 – 12 | 7 |
| antioxidant / process stabilizer packagehindered phenol + phosphite | 0.05 – 0.3 | 0.15 |
| slip / antiblock (film grades)erucamide + silica/talc | 0 – 0.5 | 0.2 |
| carbon black (black grades)UV protection, ASTM D1248 Class C | 0 – 2.5 | 2.3 |
| ethylene (C2H4) repeat unitlinear backbone | ≥ 88 (balance) | — |
LLDPE XL — frequently asked
What is LLDPE XL used for?
LLDPE XL is typically used for stretch and shrink film, flexible packaging film, cable insulation, rotomolded tanks and agricultural film. In short: tear-tough LDPE upgrade; standard rotomoulding resin; excellent heat-fusion weldability.
What is the yield strength of LLDPE XL?
LLDPE XL has a typical yield strength of 14 MPa (2.03 ksi) and a tensile strength of 20 MPa (2.9 ksi) — weaker than 84% of polymer grades. Strength varies by condition: see the 6 listed tempers.
Is LLDPE XL easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 78% of polymer grades). Turns, mills and drills, but the material is soft and gummy: use sharp large positive-rake tools, high spindle speed, generous feed and air cooling to clear chips and avoid heat distortion. Dimensions drift with temperature and internal stress, so it is unsuitable for tight-tolerance machined parts.
Can LLDPE XL be welded?
Not readily — weldability is rated not recommended (10/100). Heat fusion is excellent — hot-plate, hot-gas rod, extrusion welding, heat sealing and ultrasonic or RF welding (RF needs polar additives) all work. Only crosslinked XL grades cannot be re-welded.
What surface finishes work on LLDPE XL?
The non-polar surface must be corona-, flame- or plasma-treated to at least 38 dyn/cm before printing, coating or adhesive bonding. Plating is not possible; colour with masterbatch rather than paint.
Can LLDPE XL be formed, bent or molded?
Processed mainly by blown or cast film, injection moulding, rotomoulding and extrusion. Melt strength is lower than LDPE, so blown film needs higher back pressure and air-ring adjustment; shrinkage is 1.5–3%, and rotomoulded wall thickness should be compensated for about 3% shrink.
What is the maximum service temperature of LLDPE XL?
LLDPE XL is rated for continuous use to about 105°C (221 °F), and briefly to 135°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- ASTM D1248 — Polyethylene Plastics Extrusion Materials — ASTM International (2016)
- ASTM D638 / D790 / D1238 / D256 test methods — ASTM International (2022)
- Engineered Materials Handbook Vol. 2: Engineering Plastics — ASM International (1988)
- CAMPUS / UL Prospector polyethylene datasheets — CAMPUS Consortium / UL (2024)
- LLDPE film, injection and rotomoulding grade datasheets — Dow / ExxonMobil / SABIC / Borealis / Sinopec (2024)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.