Sponge Silicone Sheet
VMQ silicone sheet with a cellular structure of closed — non-interconnected — cells that prevent the passage of water, air and dust. It combines the thermal and chemical resistance of solid silicone with the compressibility, thermal insulation and lightness of a cellular material. It seals with very low closure forces, absorbs surface irregularities of the mating faces and maintains its recovery capability after thousands of compression cycles.
When a seal needs to close with little force — an oven door, an equipment lid, an access panel — solid silicone is not the best option. Its hardness demands high bolt loads to achieve a seal, and if the mating surface has irregularities or wide tolerances, the solid gasket does not conform. The result: leaks, condensation, loss of thermal insulation.
Closed-cell sponge silicone solves that problem. Its cellular structure allows it to compress to 50–70% of its thickness with very low forces, conforming to surface irregularities that a solid gasket cannot absorb. The closed cells (non-interconnected) act as independent air chambers: they do not absorb water, do not allow gas to pass and provide additional thermal insulation. And because the base is VMQ silicone, the material maintains these properties from –60 °C to +200 °C, with total resistance to UV, ozone and weathering.
Available in multiple grades according to the application: industrial standard for general sealing, food-grade FDA for the food and pharmaceutical industries, fire-retardant EN 45545-2 for rail and transport, metal-detectable for production lines with metal detectors, and hi-recovery for applications with frequent opening and closing cycles.
Sponge or solid? How to choose
The general rule: if you can guarantee machined sealing surfaces, controlled closure forces and tight tolerances, solid silicone seals better in the long run. If the surfaces are irregular, the closure force is limited (manual closure, hinges, clips), the tolerances are wide or you need additional thermal insulation, sponge is the right choice. Typical sponge applications: equipment doors, quick-release lids, access panels, interfaces between different materials, seals for electrical or electronic enclosures, outdoor luminaire gaskets.
Which grade do you need?
Locate your application and the recommended grade.
| Requisito | Formulación | Serie | Proceso |
|---|---|---|---|
| Industrial oven door gasket | Standard medium | ~250 kg/m³ · 6–12 mm | Custom cut + adhesive |
| IP65 electrical enclosure seal | Standard medium | ~250 kg/m³ · 3–5 mm | CNC die-cut to drawing |
| Food cold room door gasket | Food-grade Series 15 | FDA · 6–10 mm | Custom cut + adhesive |
| Food hopper lid seal | Food-grade Series 15 | FDA · 4–6 mm | Die-cut to drawing |
| Railway carriage door gasket | Fire-retardant Series 33 | EN 45545 · 5–10 mm | Custom cut + adhesive |
| Train interior panel seal | Fire-retardant Series 33 | EN 45545 · 3–5 mm | Die-cut to drawing |
| Food oven door gasket with metal detector | Metal-detectable | FDA + ferrite · 6–12 mm | Custom cut + adhesive |
| Industrial luminaire seal | UL 94 V-0 | ~250 kg/m³ · 2–4 mm | CNC die-cut to drawing |
| Quick-cycle autoclave lid | Hi-Recovery | Hi-Recovery · 4–8 mm | Die-cut to drawing |
| Industrial equipment thermal insulation | Standard soft | ~200 kg/m³ · 10–25 mm | Custom cut |
A sponge silicone grade for every requirement
Industrial standard — medium density
General-purpose closed-cell sponge silicone. Medium density (~250 kg/m³), good compressibility, excellent elastic recovery. The most versatile grade for industrial seals where food-grade or fire-retardant certification is not required. Standard red or white colour.
Food-grade FDA — Series 15
Platinum-cured cellular silicone with FDA 21 CFR 177.2600, BfR IX/XV and EC 1935/2004 certified raw materials. Density between 0.5 and 0.8 g/cm³ depending on thickness. Post-cured to eliminate residual volatiles. Light blue or white colour. For compressible seals in food and pharmaceutical processing equipment where the gasket is in contact with product or in a contamination risk zone.
Fire-retardant EN 45545-2 — Series 33
Platinum-cured cellular silicone with enhanced fire resistance. Compliant with EN 45545-2 version 2020, requirement sets R22 and R23 at hazard levels HL1 and HL2. Low smoke emission and low toxicity. Colours: black (approx. RAL 9017), grey, cream. The reference grade for cellular seals in railway rolling stock, metro, tram and stations.
Metal-detectable
Closed-cell sponge silicone with metallic ferrite particles. Detectable by industrial metal inspection equipment. Blue or light grey colour. For compressible seals in food and pharmaceutical plants with in-line metal detectors. Combines the compressibility of sponge with the safety of detectability.
Hi-Recovery
Grade formulated for applications with frequent opening and closing cycles. Compression set (permanent deformation) significantly lower than that of standard sponge. The material recovers its original thickness even after long periods of compression at high temperature. For seals that are opened and closed several times a day.
Fire-retardant UL 94 V-0
Sponge silicone grade with self-extinguishing capability per UL 94 V-0. For applications where UL flammability classification is required but railway EN 45545-2 certification is not. Grey colour. Suitable for electrical enclosures, control panels, industrial luminaires and electronic equipment.
Density determines seal firmness
The density of the sponge determines its resistance to compression. A soft sponge (200 kg/m³) compresses with very little force — ideal for manual closures and very irregular surfaces. A firm sponge (400–500 kg/m³) requires more force but offers greater pressure resistance and better sealing against fluids. Medium density (250 kg/m³) is the balance point for most applications.
Soft — ~200 kg/m³
~200 kg/m³Low density, maximum compressibility. Deforms with minimal forces. Ideal for seals where closure force is limited (clip closures, small hinges, manual assembly) or where surfaces have very wide tolerances.
- Density
- ~200 kg/m³
- Typical compression
- 25% deflection at 15–35 kPa
- Water absorption
- < 3%
Availability: Standard and food-grade. Thicknesses 1.5 to 25 mm.
Medium — ~250 kg/m³
~250 kg/m³The most versatile grade. Balance between compressibility and resistance. Compresses with moderate force, recovers well, seals effectively against water and dust. The industry standard for door, panel and enclosure gaskets.
- Density
- ~250 kg/m³
- Typical compression
- 25% deflection at 35–70 kPa
- Water absorption
- < 3%
Availability: All grades available. Thicknesses 1.5 to 25 mm.
Firm — ~400–500 kg/m³
~400–500 kg/m³High density, greater resistance to compression and pressure. Compresses less than the soft and medium grades but withstands light hydrostatic or pneumatic pressure without excessive deformation. Better long-term dimensional stability under load.
- Density
- ~400–500 kg/m³
- Typical compression
- 25% deflection at 70–170 kPa
- Water absorption
- < 1%
Availability: Standard, fire-retardant, hi-recovery. Thicknesses 1.5 to 12 mm.
Standard thicknesses: 1.5 · 2 · 3 · 4 · 5 · 6 · 8 · 10 · 12 · 15 · 20 · 25 mm. Standard roll width 1,000 mm. Surface finish: thin skin on both faces that improves watertightness and allows adhesive backing. Thickness tolerance ±10% for calendered rolls.
Cellular formulations for every standard
Cellular food-grade — Series 15 (platinum)
Platinum-cured cellular silicone. Raw materials certified FDA 21 CFR 177.2600, BfR IX/XV, EC 1935/2004. Density variable between 0.5 and 0.8 g/cm³ depending on thickness (500–800 kg/m³). Tensile ≥ 3 MPa, elongation ≥ 600%, tear ≥ 15 kN/m. Excellent mechanical properties for a cellular silicone, with good watertightness and elastic recovery.
Food industry, pharmaceutical, dairy, beverages, cosmetics, environments with food-contact requirements.
| Property | Value | Standard |
|---|---|---|
| Tensile strength (MPa min) | ≥ 3 | ISO 37 |
| Elongation at break (% min) | ≥ 600 | ISO 37 |
| Tear strength (kN/m min) | ≥ 15 | ISO 34-1 |
| Density | 0.5–0.8 g/cm³ | ISO 2781 |
| Temperature range | –60 to +200 °C | — |
Data: Series 15 Progress Silicones. Platinum cure. RAL colours to order (verify compatibility with food-grade certification per colorant). Tolerances ISO 3302 E1 (extrusion).
Cellular fire-retardant — Series 33 (platinum, EN 45545-2)
Platinum-cured cellular silicone with enhanced fire resistance. Tested per EN 45545-2 version 2020 at thicknesses of 3 mm and 10 mm. Compliant with requirement sets R22 and R23 at hazard levels HL1 and HL2. Oxygen index 29%, maximum optical smoke density (Ds max) 62.1, toxicity index (ITCPNL) 0.05. Low smoke emission and low toxicity — well below the regulatory limits.
Railway rolling stock, metro, tram, stations, tunnels, buses, public transport with EN 45545-2 requirements.
| Test | Standard | Result | R22/R23 requirement |
|---|---|---|---|
| Oxygen index (%) | EN ISO 4589-2 | 29 | ≥ 26 (HL2) |
| Ds max (smoke) | EN ISO 5659-2 (25 kW/m²) | 62.1 | ≤ 300 (HL2) |
| ITCPNL (toxicity) | EN 17084 (600 °C) | 0.05 | ≤ 1.2 (HL2) |
| Levels achieved | — | HL1 and HL2 | — |
Data: Series 33 Progress Silicones. Testing conducted in an external laboratory. Tested thicknesses: 3 mm and 10 mm. Colours: black (RAL 9017 approx.), grey, cream. Tolerances ISO 3302 E3 (cellular extrusion).
Industrial standard cellular
General-purpose closed-cell cellular silicone. Peroxide or platinum cure depending on availability. Multiple densities (200–500 kg/m³). Surface finish with skin on both faces. Good UV, ozone and weathering resistance. Excellent compression set — recovers its original thickness after prolonged compression.
General industry, HVAC, electrical enclosures, lighting, construction, automotive, aerospace, any compressible seal without specific food-grade or fire-retardant requirements.
| Property | Soft (~200) | Medium (~250) | Firm (~400–500) |
|---|---|---|---|
| 25% deflection (kPa) | 15–35 | 35–70 | 70–170 |
| Water absorption (%) | < 3 | < 3 | < 1 |
| Temperature range (°C) | –60 to +200 | –60 to +200 | –60 to +200 |
| Compression set 70h/100°C (%) | < 25 | < 25 | < 20 |
Indicative values for standard calendered sponge. The compression set of silicone sponge is significantly better than that of EPDM or neoprene sponge at high temperature. Standard colours: red, white, grey, black.
Platinum-cured cellular silicone. Raw materials certified FDA 21 CFR 177.2600, BfR IX/XV, EC 1935/2004. Density variable between 0.5 and 0.8 g/cm³ depending on thickness (500–800 kg/m³). Tensile ≥ 3 MPa, elongation ≥ 600%, tear ≥ 15 kN/m. Excellent mechanical properties for a cellular silicone, with good watertightness and elastic recovery.
Food industry, pharmaceutical, dairy, beverages, cosmetics, environments with food-contact requirements.
| Property | Value | Standard |
|---|---|---|
| Tensile strength (MPa min) | ≥ 3 | ISO 37 |
| Elongation at break (% min) | ≥ 600 | ISO 37 |
| Tear strength (kN/m min) | ≥ 15 | ISO 34-1 |
| Density | 0.5–0.8 g/cm³ | ISO 2781 |
| Temperature range | –60 to +200 °C | — |
Data: Series 15 Progress Silicones. Platinum cure. RAL colours to order (verify compatibility with food-grade certification per colorant). Tolerances ISO 3302 E1 (extrusion).
Platinum-cured cellular silicone with enhanced fire resistance. Tested per EN 45545-2 version 2020 at thicknesses of 3 mm and 10 mm. Compliant with requirement sets R22 and R23 at hazard levels HL1 and HL2. Oxygen index 29%, maximum optical smoke density (Ds max) 62.1, toxicity index (ITCPNL) 0.05. Low smoke emission and low toxicity — well below the regulatory limits.
Railway rolling stock, metro, tram, stations, tunnels, buses, public transport with EN 45545-2 requirements.
| Test | Standard | Result | R22/R23 requirement |
|---|---|---|---|
| Oxygen index (%) | EN ISO 4589-2 | 29 | ≥ 26 (HL2) |
| Ds max (smoke) | EN ISO 5659-2 (25 kW/m²) | 62.1 | ≤ 300 (HL2) |
| ITCPNL (toxicity) | EN 17084 (600 °C) | 0.05 | ≤ 1.2 (HL2) |
| Levels achieved | — | HL1 and HL2 | — |
Data: Series 33 Progress Silicones. Testing conducted in an external laboratory. Tested thicknesses: 3 mm and 10 mm. Colours: black (RAL 9017 approx.), grey, cream. Tolerances ISO 3302 E3 (cellular extrusion).
General-purpose closed-cell cellular silicone. Peroxide or platinum cure depending on availability. Multiple densities (200–500 kg/m³). Surface finish with skin on both faces. Good UV, ozone and weathering resistance. Excellent compression set — recovers its original thickness after prolonged compression.
General industry, HVAC, electrical enclosures, lighting, construction, automotive, aerospace, any compressible seal without specific food-grade or fire-retardant requirements.
| Property | Soft (~200) | Medium (~250) | Firm (~400–500) |
|---|---|---|---|
| 25% deflection (kPa) | 15–35 | 35–70 | 70–170 |
| Water absorption (%) | < 3 | < 3 | < 1 |
| Temperature range (°C) | –60 to +200 | –60 to +200 | –60 to +200 |
| Compression set 70h/100°C (%) | < 25 | < 25 | < 20 |
Indicative values for standard calendered sponge. The compression set of silicone sponge is significantly better than that of EPDM or neoprene sponge at high temperature. Standard colours: red, white, grey, black.
From the sheet to your sponge gasket
We supply sponge sheet in roll form or as custom-cut and die-cut parts. For three-dimensional geometries (cords, profiles, cellular tubes), we supply cellular silicone extruded in Series 15 and 33.
Application sectors
Food & Beverage
Food-grade FDA sponge for door gaskets, lids and panels on processing equipment.
Rail
Fire-retardant EN 45545-2 sponge for door, window and panel seals on trains and metros.
Lighting
IP65/67 sponge gaskets for sealing industrial and outdoor luminaires.
General Industry
Compressible seals for electrical enclosures, HVAC ducts and industrial equipment.
Related products
Food-Grade Silicone Sheet
Solid FDA sheet for flat gaskets and seals with controlled closure force.
Metal-Detectable Silicone Sheet
Sheet with ferrite particles detectable by in-line inspection equipment.
Conductive Silicone Sheet
Carbon-loaded silicone sheet for ESD protection.
TIXAN'AIR® Inflatable Seals
When sponge is not enough: pneumatic sealing with controlled deflection.
Need sponge silicone for your seal?
Tell us the application (equipment, temperature, closure force, opening frequency), the required standard (food-grade, fire-retardant, IP), the dimensions (thickness, length, width or gasket drawing) and the quantity. We recommend the appropriate grade and density and provide a quotation with the complete technical documentation.
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