Both are polyethylene and closed-cell; nothing chemical separates them. EPE (pearl foam) is extruded into sheet and roll, then cut, die-punched and laminated into a shape. Beaded EPE is the same polyethylene supplied as beads, filled into a steam mold and formed in one piece. In the table below, rows governed by the polymer read the same; rows governed by forming open a gap.
We supply both routes out of the same plant. Figures are typical property ranges for finished parts, not guaranteed limits; what your part reaches depends on geometry, thickness and achieved density.
The chemistry is identical: same backbone, same closed cells, same 80 °C ceiling, same recycling stream. The choice is between a knife and a mold. EPE gets its shape by subtraction: sheet cut, punched and glued. Beaded EPE gets it by addition: beads fill a cavity and fuse into one piece.
The rows where the two columns are identical are the polymer: service temperature, absorption efficiency, flame, chemical and weather behaviour. The rows where they separate are the forming method: load, rebound, tensile strength, hardness, density ceiling, cold limit.
| Property | EPE | Beaded EPE | What the gap means for your part |
|---|---|---|---|
| Molded density (kg/m³) | 20–45 | 20–74 | Same floor, different ceiling. Extruded sheet is limited by what the extrusion line can foam and hold together in a continuous web; a mold cavity is packed with beads and can be driven to 74 kg/m³. Below 45 the two windows overlap; above it, only the molded route exists. |
| Compression stress at 10% strain (kPa) | 22–88 | 44.8–241.3 | The clearest consequence of forming: about 2.7 times more load at the top of the range. Part of that is the density ceiling above, and part is geometry: a molded rib carries load directly, where a cut-and-laminated stack carries it across bond lines. If the part has to hold a payload rather than pad it, this row usually ends the discussion. |
| Energy return / rebound (%) | 30–35 | 50 | Cut sheet gives back roughly a third of the impact energy; the molded bead gives back half. Over one drop that is barely visible. Over fifty trips it is the difference between an insert that still locates the payload and one that has flattened into a pad. |
| Long-term service temperature (°C) | 80 | 80 | Identical, and that is the point. The heat ceiling belongs to the polyethylene, not to the machine that shaped it. Neither route buys you temperature the other lacks, so a hot application never chooses between these two; it chooses a different polymer. |
| Minimum service temperature (°C) | −60 | −70 | Both are deep-freeze materials, and only 10 °C separates them. It matters at the extreme edge: cold-room fixtures and frozen logistics specified below −60 °C are a molded-bead conversation. |
| Thermal conductivity, W/(m·K) | 0.039–0.044 | 0.0346–0.0433 | Effectively the same insulation, from the same closed cells in the same polymer. If a part is chosen for thermal reasons, this row will not decide it. Wall thickness and sealing will, and neither route has an advantage there. |
| Tensile strength (kPa) | 282–478 | 275.8–827.4 | Nearly double at the top. The molded part resists tearing at pocket walls, clip features and thin sections where a laminated sheet part would first fail at a bond line. At the light end the two are level, because at 20 kg/m³ both are simply thin-walled polyethylene. |
| Hardness (Asker-C) | 25–40 | 25–55 | Both start at the same soft 25, which is why both are safe against finished surfaces. Only the molded route continues to 55, where the part stops being a cushion and starts being a fixture that positions something accurately. |
| Energy absorption efficiency (%) | 60–70 | 60–70 | Identical again, and worth pausing on. Efficiency is how much of the area under the stress-strain curve the foam actually uses, and that is a cell-structure property of closed-cell polyethylene. Forming changes how much load the part can take, not how well the foam converts it. |
| Flame behaviour | FMVSS 302 passed on standard grades, burn rate 35–55 mm/min | FMVSS 302 passed across the full density range | Same polymer, same result. Neither route reaches a rating the other cannot hold, and flame-retardant grades are available on both sides. Tell us the standard your programme is audited against and we will confirm in writing what the grade holds. |
| Antistatic | Antistatic grade available, surface resistivity 1e9–1e12 Ω/□ | Permanent antistatic beads, surface resistivity 1e11 Ω/□ | Both routes reach the antistatic band. The molded bead carries the property in the bead itself rather than as an applied treatment, which is what matters when a returnable insert is wiped down repeatedly over years of service. |
Same dataset, all thirteen materials
Draw a section through the part. If every feature can be reached by a knife coming straight down through flat stock, EPE will make it without a tool. An undercut, a re-entrant pocket or a rib that changes height cannot. Stacking cut layers approximates the form, but each bond line can peel and each layer adds a tolerance: beyond about three layers, molding is simpler.
At 10% strain, cut EPE tops out at 88 kPa and the molded bead reaches 241.3 kPa, 2.7 times as much. Extrusion stops around 45 kg/m³ where a mold cavity packs to 74, and in a molded part the load runs through a solid rib rather than across adhesive planes. If the foam pads a surface, cut sheet is enough; if it supports a mass, mold it.
Cut EPE returns 30–35% of the energy it absorbs; the molded bead returns 50%. On a single drop that is academic, since both survive. Across fifty trips it decides whether the pocket still holds the part within a millimetre, which is why a returnable insert is normally quoted as a molded part.
Long-term service temperature is 80 °C for both; short-term stability runs to 90 °C for the sheet and 100 °C for the molded part. That ceiling belongs to the polyethylene, so above 80 °C neither is your material. The cold end separates a little: −60 °C cut against −70 °C molded.
Both routes start at 20 kg/m³, so at the light end decide on shape and volume, not numbers. Above 45 kg/m³ extrusion stops and only the molded route continues, to 74: the 241.3 kPa load and the 55 Asker-C hardness are reachable only through a mold. If you need 30 kg/m³ and the shape is simple, a mold buys very little.
Beaded EPE needs a steam mold: designed, cut and tried, with a minimum order quantity, and a geometry change is a change to the tool. EPE needs none of it. Sheet comes from stock, the part is a cutting program and a die, and a revision is a new file. Prototypes and twenty-part families are almost always cut.
Ten application families and the route we start from. The reason is almost always shape, volume or trips.
| Application | Start from | Typical density | Why |
|---|---|---|---|
| Surface protection sheet and layer pads | EPE | 20–30 kg/m³ | Flat, soft, non-abrasive, cut to size from stock. There is no shape to mold, so a mold would buy nothing at all. |
| Die-cut liners for simple cartons | EPE | 25–35 kg/m³ | A profile a die can punch in one stroke. Fast, low minimum quantity, and the design can change between production runs. |
| Laminated multi-layer inserts | EPE | 30–45 kg/m³ | Two or three cut layers bonded into a stepped cavity. Works well up to about three layers; past that, molding is usually the simpler part. |
| Shaped inserts with pockets and undercuts | Beaded EPE | 24–37 kg/m³ | Re-entrant features and draft that a knife cannot reach. One piece, no bond lines, repeatable from the first shot to the last. |
| Returnable trays and dunnage | Beaded EPE | 30–45 kg/m³ | Fifty percent energy return and pocket dimensions that hold across hundreds of trips. The first impact is not the one being designed for. |
| Load-bearing blocks, spacers and fixtures | Beaded EPE | 45–74 kg/m³ | 241.3 kPa at 10% strain and 55 Asker-C, both of which live above the ceiling that extrusion can reach. |
| Consumer electronics presentation trays | Beaded EPE | 20–30 kg/m³ | The soft surface of polyethylene with a molded pocket that positions the device. Unboxing quality is geometry, and geometry is a mold. |
| Deep-freeze handling and cold-room parts | Beaded EPE | 30–45 kg/m³ | Service to −70 °C against −60 °C, plus the toughness to be handled with gloves at that temperature without splitting. |
| Prototype, pilot and short-run packaging | EPE | 20–45 kg/m³ | No tool, no tooling lead time, and a revision costs a cutting file. Move to molding once the geometry and the volume have both settled. |
| Antistatic packaging for boards and modules | EPE flat · Beaded EPE shaped | 20–37 kg/m³ | Both routes reach the antistatic band, so this one goes back to shape: a bag, sheet or pad is cut, a board carrier with slots is molded. |
EPE is supplied as sheet at 20 / 25 / 30 / 35 / 45 kg/m³; Beaded EPE is molded at seven densities from 20 to 74 kg/m³. Past 45 kg/m³ there is no choice left. EPE compression is stated at 10% strain to ISO 844, Beaded EPE to ASTM D3575.
| Density grade | Route | Density (kg/m³) | Compression at 10% strain (kPa) | Where it belongs |
|---|---|---|---|---|
| 30 kg/m³ | EPE | 30 | 44 | The workhorse sheet grade: liners, wraps, layer pads and die-cut profiles for light and medium payloads. |
| 45 kg/m³ | EPE | 45 | 88 | The top of the extruded window. Laminated inserts and heavier cut dunnage, and the last point where the two routes still meet. |
| 20 kg/m³ | Beaded EPE | 20 | 44.8 | The lightest molded grade: soft shaped trays where the geometry matters more than the load. |
| 24 kg/m³ | Beaded EPE | 24 | 55.2 | Shaped electronics and appliance inserts. Already carrying more than cut sheet at 30 kg/m³. |
| 30 kg/m³ | Beaded EPE | 30 | 70.3 | The direct comparison point: 70.3 kPa molded against 44 kPa cut, at exactly the same density and the same polymer. |
| 37 kg/m³ | Beaded EPE | 37 | 91 | Returnable trays and dunnage with real payload. Past everything the extruded window can offer. |
| 45 kg/m³ | Beaded EPE | 45 | 115.8 | The other 45 kg/m³ grade in this table, carrying 115.8 kPa where the cut sheet carries 88. Same weight of polymer, more of it working. |
| 67 kg/m³ | Beaded EPE | 67 | 202.7 | Structural territory. Fixtures, spacers and blocks that position a mass rather than cushion it. |
| 74 kg/m³ | Beaded EPE | 74 | 241.3 | The stiffest grade on this page, and unreachable by any cutting route. This row is the whole argument for a mold in one line. |
A Beaded EPE part begins with a steam mold, an EPE part with a cutting program: one change means new steel, the other a new file. Cut the first parts, prove the geometry and the drop performance, then mold once the design has stopped moving.
If the pair above is not quite yours, one of these is.
| Comparison | The decision it settles |
|---|---|
| EPP vs Beaded EPE foam | Once you have decided to mold, which polymer goes in the cavity. Rigidity and repeated impact against soft wrap, surface safety and service down to −70 °C. |
| EPP vs EPS foam | The other classic molded pair: recovery against cost. Whether the part is struck once or many times. |
| All foam materials, ranked | Every material we supply ordered by load, temperature, resilience and cost position, so you can see where these two sit in the whole field. |
Chemically, yes. Both are closed-cell polyethylene foam, and the property table shows it: long-term service temperature is 80 °C on both sides, energy absorption efficiency is 60–70% on both sides, and chemical resistance, weathering and end-of-life read the same. What separates them is how the part is made. EPE is extruded into sheet and roll, then cut, die-punched and laminated into shape. Beaded EPE arrives as beads that are filled into a steam mold and formed in one piece.
Beaded EPE, by roughly 2.7 times at the top of the range: 241.3 kPa at 10% strain against 88 kPa for EPE. Two things open that gap, and both come from the forming method. The molded route reaches 74 kg/m³ where extruded sheet stops at 45, and a molded shape puts polymer into ribs and walls that carry load directly, where a cut-and-laminated part carries it across bond lines. Nearer the bottom of the density window the two are much closer.
No, and that is the main reason to choose it. EPE parts are cut, die-punched, heat-formed and laminated from stock sheet, so there is no steam mold to pay for and no tooling lead time to wait out. Revising the design means revising the cutting program rather than cutting a new tool, and minimum order quantities stay low. Beaded EPE does need a mold, and that mold is exactly what buys the one-piece geometry, the pockets and undercuts, and the higher load capacity.
It sits lower in our cost ranking: across the thirteen foam materials we supply, EPE is in second position and Beaded EPE in fourth. The bigger difference is structural rather than per part. EPE carries no tooling step at all, which keeps short runs and long part lists economical, while Beaded EPE spreads a mold across the programme and earns it back through load capacity, one-piece geometry and reuse. Send us the part and the annual quantity and we will cost both routes.
Both are rated to 80 °C for long-term service, because that ceiling belongs to the polyethylene rather than to the forming method. The cold end differs slightly: EPE is specified to −60 °C and Beaded EPE to −70 °C. So heat resistance never decides between these two, and only deep-freeze work below −60 °C pushes the choice toward the molded bead.
Beaded EPE, in almost every case. A returnable insert is struck repeatedly and has to hold its pocket dimensions across dozens or hundreds of trips, and the molded bead returns 50% of the impact energy against 30–35% for cut sheet. It also comes out as one piece, with no bond lines to peel apart under repeated handling. EPE remains the better answer for the single-trip liner that goes into the carton once and is recycled at the far end.
You do not have to name a route. Send the geometry, the payload, the annual quantity and the number of trips. We come back with a process, a density and a sample plan within 48 hours.