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LDPE FOAM

Grade

ASTM D1248 Type I · ISO PE-LD

FOAM = closed-cell LDPE foam

Chemically or physically blown closed-cell foam for protective packaging, gaskets and thermal insulation.

Values for the FOAM condition

Other LDPE grades and fills

LDPE is listed in 7 conditions; see the grade overview at LDPE.

Compare all 7 grades and fillsHide
Grade · open for datasheetBest forYield MPaTensile MPaElong. %Hardness
FOAMThis page
Closed-cell LDPE foam
Chemically or physically blown closed-cell foam for protective packaging, gaskets and thermal insulation.0.35100
Extrusion coating / lamination grade
Broad-MWD resin for high-speed coating of paper, board and foil; chosen for neck-in control and hot-tack adhesion.91140045 Shore D
Injection moulding grade
High-MFR, lower-molecular-weight resin for thin-wall soft mouldings such as closures, liner caps and squeeze parts.101020046 Shore D
FR V-0
Use where UL 94 V-0/V-2 or low-smoke halogen-free cable compounds are required; heavy filler loading cuts elongation sharply.101015052 Shore D
Carbon-black pigmented (2–2.5% CB) grade
Best low-cost outdoor durability — 2.5% well-dispersed carbon black for pipe sleeving, geomembrane and cable jacketing.101140048 Shore D
Antistatic / conductive carbon-filled grade
Carbon-black or antistat-loaded compound for electronics packaging film, explosive-atmosphere liners and cable semicon layers.111225050 Shore D
Cross-linked LDPE
Cross-linked network for LV/MV cable insulation and heat-shrink; raises continuous rating to ~90 °C and kills stress cracking, but the cured part cannot be remelted.1745050 Shore D

What is LDPE FOAM?

LDPE FOAM is LDPE in the FOAM grade — chemically or physically blown closed-cell foam for protective packaging, gaskets and thermal insulation. LDPE FOAM has a yield strength of 10 MPa (1.45 ksi) and a tensile strength of 0.35 MPa (0.0508 ksi) — weaker than 91% of polymer grades. Elongation at break is 100% and the elastic modulus is 0 GPa (2.9×10⁻⁴ Msi). LDPE FOAM has a density of 0.04 g/cm³ (0.0013 lb/in³), lighter than 92% 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 — 2.1 kg CO₂/kg, better than 94% of polymer grades
  • Lightweight — 0.04 g/cm³ (0.0013 lb/in³), better than 92% of polymer grades
  • Forms and bends easily — 90/100, better than 91% of polymer grades

Limitations

  • Low stiffness — 0 GPa (2.9×10⁻⁴ Msi), worse than 95% of polymer grades
  • High mold shrinkage — 2.5%, worse than 93% of polymer grades
  • Low strength — 10 MPa (1.45 ksi), worse than 91% of polymer grades
  • Degrades in UV without stabilisers — 20/100, worse than 88% of polymer grades
  • Poor heat conductor — 0.04 W/m·K (0.0231 BTU/hr·ft·°F), worse than 87% of polymer grades

LDPE FOAM properties

Typical room-temperature values for LDPE FOAM; 17 are specific to this condition. Other listed values are LDPE reference data and may not represent this condition. Bars are the position among polymer grades.

Physical7

LDPE FOAM has a density of 0.04 g/cm³ (0.0013 lb/in³), lighter than 92% of polymer grades. Its glass-transition temperature is -110°C (-166 °F).

Density0.04 g/cm³0 lb/in³
Melting Temperature (Tm)110°C230 °F
Glass Transition (Tg)-110°C-166 °F
Water Absorption (24 h)0.01%
Water Absorption (Saturation)0.02%
Refractive Index1.51
Light Transmission80%

Mechanical17

LDPE FOAM has a yield strength of 10 MPa (1.45 ksi) and a tensile strength of 0.35 MPa (0.0508 ksi) — weaker than 91% of polymer grades. Elongation at break is 100% and the elastic modulus is 0 GPa (2.9×10⁻⁴ Msi).

Elastic (Young's) Modulus0 GPa2.9×10⁻⁴ Msi
Shear Modulus0.08 GPa0.01 Msi
Bulk Modulus2 GPa0.26 Msi
Poisson's Ratio0.45
Tensile Strength (Ultimate)0.35 MPa0.05 ksi
Yield Strength (0.2% offset)10 MPa1.5 ksi
Elongation at Break100%
Compressive Strength0.06 MPa0.01 ksi
Compressive Modulus0.2 GPa0.03 Msi
Flexural Strength10 MPa1.5 ksi
Flexural Modulus0.25 GPa0.04 Msi
Shear Strength0.15 MPa0.02 ksi
Fracture Toughness (K_IC)1.4 MPa·√m1.3 ksi·√in
Izod Impact, Notched800 J/m15 ft·lbf/in
Hardness, Shore A93 Shore A
Hardness, Shore D47 Shore D
Tear Strength0.6 kN/m3.4 lbf/in

Thermal11

LDPE FOAM is rated for continuous service to 70°C (158 °F). It conducts heat at 0.04 W/m·K (0.0231 BTU/hr·ft·°F), worse than 87% of polymer grades. Thermal expansion is 190 µm/m·K (105.6 µin/in·°F).

Thermal Conductivity0.04 W/m·K0.02 BTU/hr·ft·°F
Specific Heat Capacity2,100 J/kg·K0.5 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)190 µm/m·K106 µin/in·°F
Max Service Temperature (continuous)70°C158 °F
Min Service Temperature-60°C-76 °F
Heat Deflection Temp. @ 0.45 MPa47°C117 °F
Heat Deflection Temp. @ 1.8 MPa34°C93 °F
Vicat Softening Point (B50)50°C122 °F
Flammability (UL 94)HB (FR-treated foams available)
Limiting Oxygen Index18%
Max Service Temperature (short-term)90°C194 °F

Electrical7

LDPE FOAM is an electrical insulator with a dielectric strength of 25 kV/mm (635 V/mil) and a resistivity of 1×10¹⁴ Ω·m.

Electrical Resistivity1×10¹⁴ Ω·m3.94×10²¹ µΩ·in
Dielectric Strength25 kV/mm635 V/mil
Dielectric Constant (1 MHz)2.28
Dissipation Factor (1 MHz)3×10⁻⁴
Volume Resistivity1×10¹⁶ Ω·cm
Surface Resistivity1×10¹⁵ Ω
Comparative Tracking Index (CTI)600 V

Chemical & Environmental3

Corrosion resistance is excellent (85/100), better than 65% of polymer grades. UV resistance is poor.

Corrosion ResistanceExcellent85/100
UV / Weathering ResistancePoor20/100
Chemical Resistance SummaryExcellent against water, brines, dilute and most concentrated acids/alkalis, alcohols; swells in aliphatic/aromatic hydrocarbons and chlorinated solvents above 40 °C; attacked by strong oxidizers (fuming HNO3); susceptible to environmental stress cracking with detergents and surfactants.

Sustainability4

Producing a kilogram of LDPE FOAM takes about 80 MJ of energy and emits 2.1 kg of CO₂ — less than 85% of polymer grades. Typical recycled content is 10%.

Embodied Energy (primary production)80 MJ/kg34,394 BTU/lb
Embodied Carbon (primary production)2.1 kg CO₂/kg
Embodied Water120 L/kg14.4 gal/lb
Typical Recycled Content10%

Manufacturability8

LDPE FOAM's machinability is poor (30/100, worse than 87% of polymer grades); weldability very good (70/100); formability excellent (90/100).

MachinabilityPoor30/100
WeldabilityVery good70/100
Formability (cold)Excellent90/100
PolishabilityPoor30/100
Mold Shrinkage2.5%
Melt Flow Rate2 g/10 min
Processing Melt Temperature (typ.)190°C374 °F
Mold Temperature (typ.)30°C86 °F

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with LDPE FOAM

Is LDPE easy to machine?

Cuts easily but is gummy and springs back — use very sharp positive-rake single-flute tools, high speed, low feed pressure, air blast, and expect poor tolerance hold (>0.2 mm) plus large thermal expansion.

Can LDPE be welded?

Excellent thermoplastic weldability: heat sealing, impulse, hot-plate, hot-gas and extrusion welding with LDPE/LLDPE rod; adhesive bonding needs corona, flame or plasma surface treatment.

Can LDPE be formed, bent or molded?

Very easy flow at 160–230 °C melt, 20–50 °C mould, low injection pressure; allow 1.5–4% shrinkage with strong direction dependence and design generous draft and thick-to-thin gating to avoid voids and sink.

What surface finishes work on LDPE?

Cannot be plated or painted without pre-treatment; use corona/flame treatment (≥38 dyn/cm) before printing, or in-mould colour, laser marking and hot stamping instead.

LDPE 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.

ElementSpec limit (wt %)Nominal
antioxidant / process stabilizer (hinder0.02 – 0.30.1
slip & antiblock (erucamide, silica) — fOmitted in injection and food-critical grades0 – 10.3
ethylene (branched homopolymer, C2H4 repHigh-pressure free-radical polymer; 20–40 short-chain branches + long-chain branching per 1000 C; crystallinity 40–55%≥ 98 (balance)

LDPE FOAM — frequently asked

What is LDPE FOAM used for?

LDPE FOAM is typically used for squeeze bottles, flexible tubing and hose, packaging film and drum liners, bottle cap liners and gaskets, wire and cable insulation and extrusion coating on paperboard. In short: flexible; low cost.

What is the yield strength of LDPE FOAM?

LDPE FOAM has a typical yield strength of 10 MPa (1.45 ksi) and a tensile strength of 0.35 MPa (0.0508 ksi) — weaker than 91% of polymer grades. Strength varies by condition: see the 7 listed tempers.

Is LDPE FOAM easy to machine?

Not especially — machinability is rated poor (30/100, worse than 87% of polymer grades). Cuts easily but is gummy and springs back — use very sharp positive-rake single-flute tools, high speed, low feed pressure, air blast, and expect poor tolerance hold (>0.2 mm) plus large thermal expansion.

Can LDPE FOAM be welded?

Yes — weldability is rated very good (70/100). Excellent thermoplastic weldability: heat sealing, impulse, hot-plate, hot-gas and extrusion welding with LDPE/LLDPE rod; adhesive bonding needs corona, flame or plasma surface treatment.

What surface finishes work on LDPE FOAM?

Cannot be plated or painted without pre-treatment; use corona/flame treatment (≥38 dyn/cm) before printing, or in-mould colour, laser marking and hot stamping instead.

Can LDPE FOAM be formed, bent or molded?

Very easy flow at 160–230 °C melt, 20–50 °C mould, low injection pressure; allow 1.5–4% shrinkage with strong direction dependence and design generous draft and thick-to-thin gating to avoid voids and sink.

What is the maximum service temperature of LDPE FOAM?

LDPE FOAM is rated for continuous use to about 70°C (158 °F), and briefly to 90°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Can FabDigit make parts in LDPE FOAM?

Yes — LDPE FOAM is available for sheet metal and injection molding; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.

Sources

  1. ASTM D4976 — Standard Specification for Polyethylene Plastics Molding and Extrusion Materials — ASTM International (2020)
  2. ISO 1872-1/-2 — Plastics: Polyethylene (PE) moulding and extrusion materials — ISO (2015)
  3. Engineered Materials Handbook Vol. 2: Engineering Plastics — ASM International (1988)
  4. CAMPUS / UL Prospector polyethylene datasets — CWFG / UL Solutions (2024)
  5. LDPE film and injection grade datasheets — Dow / ExxonMobil / SABIC / (2024)
  6. Eco-profile: Low Density Polyethylene (LDPE) — PlasticsEurope (2022)

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.