MDPE IM (Injection moulding grade)
Grade
ASTM D1248 Type II · ISO PE-MD
For thin-wall closures, housewares and caps needing easy fill; trades some ESCR and elongation for flow.
Values for the IM condition
Other MDPE grades and fills
MDPE is listed in 7 conditions; see the grade overview at MDPE.
Compare all 7 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Flame-retardant halogen-free (ATH/MDH filled) MDPE compound | For cable sheathing and enclosures needing V-0 / low-smoke halogen-free performance; heavy mineral loading cuts elongation and toughness. | 11 | 12 | 180 | 62 Shore D |
Rotomoulding grade | Choose for water/chemical tanks, kayaks and containers moulded rotationally, where flow and low-temperature impact matter. | 19 | 23 | 500 | 57 Shore D |
Crosslinkable / crosslinked MDPE | Select when service above 80 °C, creep resistance or full ESCR immunity is needed — hot-water pipe, crosslinked tanks and cable. | 19 | 23 | 400 | 57 Shore D |
PE80 pipe grade | Choose for buried gas distribution (yellow/orange) and potable water pipe requiring 50-year MRS 8.0 rating and slow-crack-growth resistance. | 20 | 27 | 800 | 59 Shore D |
UV-stabilized / carbon-black pigmented | Use for any outdoor or buried application — carbon black plus HALS gives decades of weathering life. | 20 | 25 | 650 | 59 Shore D |
Wire & cable jacketing / insulation compound | Black, antioxidant- and CB-stabilised MDPE for telecom and LV cable jackets needing moisture barrier and abrasion resistance. | 20 | 25 | 700 | 59 Shore D |
IMThis page Injection moulding grade | For thin-wall closures, housewares and caps needing easy fill; trades some ESCR and elongation for flow. | 21 | 22 | 350 | 61 Shore D |
What is MDPE IM?
MDPE IM is MDPE in the IM grade — for thin-wall closures, housewares and caps needing easy fill; trades some ESCR and elongation for flow. MDPE IM has a yield strength of 21 MPa (3.05 ksi) and a tensile strength of 22 MPa (3.19 ksi) — weaker than 79% of polymer grades. Elongation at break is 350% and the elastic modulus is 0.75 GPa (0.109 Msi). MDPE IM has a density of 0.94 g/cm³ (0.0339 lb/in³), lighter than 77% of polymer grades. Its glass-transition temperature is -110°C (-166 °F).
Advantages
- Readily welded — 95/100, better than 99% of polymer grades
- 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 — 0.4 W/m·K (0.231 BTU/hr·ft·°F), better than 93% of polymer grades
- Ductile — tolerates forming and impact — 350%, better than 84% of polymer grades
Limitations
- Limited service temperature — 65°C (149 °F), worse than 83% of polymer grades
- Hard to polish — 30/100, worse than 82% of polymer grades
- High mold shrinkage — 2%, worse than 81% of polymer grades
- Low strength — 21 MPa (3.05 ksi), worse than 79% of polymer grades
- Degrades in UV without stabilisers — 25/100, worse than 76% of polymer grades
MDPE IM properties
Typical room-temperature values for MDPE IM; 10 are specific to this condition. Other listed values are MDPE reference data and may not represent this condition. Bars are the position among polymer grades.
Physical7
MDPE IM has a density of 0.94 g/cm³ (0.0339 lb/in³), lighter than 77% of polymer grades. Its glass-transition temperature is -110°C (-166 °F).
Mechanical16
MDPE IM has a yield strength of 21 MPa (3.05 ksi) and a tensile strength of 22 MPa (3.19 ksi) — weaker than 79% of polymer grades. Elongation at break is 350% and the elastic modulus is 0.75 GPa (0.109 Msi).
Thermal11
MDPE IM is rated for continuous service to 65°C (149 °F). It conducts heat at 0.4 W/m·K (0.231 BTU/hr·ft·°F), better than 93% of polymer grades. Thermal expansion is 170 µm/m·K (94.4 µin/in·°F).
Electrical7
MDPE IM is an electrical insulator with a dielectric strength of 22 kV/mm (558.8 V/mil) and a resistivity of 1×10¹⁴ 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 MDPE IM takes about 78 MJ of energy and emits 2 kg of CO₂ — less than 88% of polymer grades. Typical recycled content is 5%.
Manufacturability8
MDPE IM's machinability is good (55/100, worse than 64% of polymer grades); weldability excellent (95/100); formability very good (80/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with MDPE IM
Is MDPE easy to machine?
Machines easily but gummy and low-modulus — use sharp high-rake tools, high speed, low feed, coolant/air blast and generous fixturing to avoid part deflection and springback.
Can MDPE be welded?
Ideal for butt fusion, electrofusion, hot-plate, hot-gas and extrusion welding; joints reach near parent-material strength — adhesive bonding requires corona/flame or plasma pretreatment.
Can MDPE be formed, bent or molded?
Processes on standard PE screws at 180–240 °C melt with 20–60 °C tools; allow 1.5–3 % shrinkage with anisotropy, and thermoform or cold-bend sheet with allowance for large elastic recovery.
What surface finishes work on MDPE?
No paint, plating or anodising possible without surface activation; pigment in the melt, use in-mould texture, laser marking or corona-treated print/label systems.
MDPE 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 comonomershort-chain branching sets density 0.926–0.940 | 0.5 – 4 | 2 |
| antioxidant / process stabiliserhindered phenol + phosphite | 0.05 – 0.5 | 0.2 |
| carbon black2.0–2.5 % in UV/pipe/cable grades only | 0 – 2.5 | 0 |
| HALS UV stabiliserweatherable grades | 0 – 0.5 | 0 |
| ethylene (repeat unit)polymer backbone | ≥ 95 (balance) | — |
MDPE IM — frequently asked
What is MDPE IM used for?
MDPE IM is typically used for gas pipe and fittings, shrink film, screw closures, carrier bags and sacks. In short: gas-pipe grade polyethylene; between LDPE and HDPE; good stress-crack resistance.
What is the yield strength of MDPE IM?
MDPE IM has a typical yield strength of 21 MPa (3.05 ksi) and a tensile strength of 22 MPa (3.19 ksi) — weaker than 79% of polymer grades. Strength varies by condition: see the 7 listed tempers.
Is MDPE IM easy to machine?
Reasonably — machinability is rated good (55/100, worse than 64% of polymer grades). Machines easily but gummy and low-modulus — use sharp high-rake tools, high speed, low feed, coolant/air blast and generous fixturing to avoid part deflection and springback.
Can MDPE IM be welded?
Yes — weldability is rated excellent (95/100). Ideal for butt fusion, electrofusion, hot-plate, hot-gas and extrusion welding; joints reach near parent-material strength — adhesive bonding requires corona/flame or plasma pretreatment.
What surface finishes work on MDPE IM?
No paint, plating or anodising possible without surface activation; pigment in the melt, use in-mould texture, laser marking or corona-treated print/label systems.
Can MDPE IM be formed, bent or molded?
Processes on standard PE screws at 180–240 °C melt with 20–60 °C tools; allow 1.5–3 % shrinkage with anisotropy, and thermoform or cold-bend sheet with allowance for large elastic recovery.
What is the maximum service temperature of MDPE IM?
MDPE IM is rated for continuous use to about 65°C (149 °F), and briefly to 90°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)
- ISO 4437 — Plastics piping systems for the supply of gaseous fuels — Polyethylene (PE) — ISO (2014)
- Engineered Materials Handbook Vol. 2: Engineering Plastics — ASM International (1988)
- CAMPUS / UL Prospector polyethylene datasheet set — CWFG / UL Solutions (2024)
- Polyethylene MDPE pipe, film and rotomoulding grade datasheets — Borealis / SABIC / Dow / Sinopec (2024)
- (PE resin spot pricing) (2026)
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.