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Silicone Foam (Sponge Rubber) EMI-COND

Additive grade

Use where an enclosure joint needs environmental sealing and EMI shielding at once; Ni/C or Ag filler drops volume resistivity to the Ω·cm range, at 0.85 g/cm³ density.

High cost $$$$

Values for the EMI-COND condition

Other Silicone Foam (Sponge Rubber) grades and fills

Silicone Foam (Sponge Rubber) is listed in 9 conditions; see the grade overview at Silicone Foam (Sponge Rubber).

Compare all 9 grades and fillsHide
Grade · open for datasheetBest forYield MPaTensile MPaElong. %Hardness
RE41/RE42
Pick when breathability, a very soft feel or high-temperature insulating padding is needed; the open cells take up water and dust, so avoid waterproof or dust-tight sealing duties.—0.615010 Shore A
Closed-cell silicone foam, soft
Choose the soft closed-cell grade (14–34 kPa at 25% deflection, 0.25 density) when thin plastic covers or sheet metal give low clamping force and must still seal at minimal compression load.—0.818012 Shore A
Thermally conductive silicone foam
Pick as a compressible thermal interface pad between battery modules and power devices, combining 0.5 W/m·K conduction with low compression stress up to 200 °C.—0.97045 Shore A
EMI-CONDThis page
Ni/C or Ag filled
Use where an enclosure joint needs environmental sealing and EMI shielding at once; Ni/C or Ag filler drops volume resistivity to the Ω·cm range, at 0.85 g/cm³ density.—18045 Shore A
FR (UL94 V-0 / HF-1) flame-retardant silicone foam
Choose for seals and insulating pads in rail transit, battery packs and electrical cabinets that must hold UL94 V-0/HF-1 or EN45545 approval, with service up to 200 °C.—113025 Shore A
SCE42Default
Closed-cell silicone foam, medium firmness
Use this medium-firmness closed-cell foam (34–62 kPa at 25% deflection) as the default gasket for enclosures, luminaires and outdoor electrical housings where clamping load is moderate.—116020 Shore A
Closed-cell silicone foam, firm
Pick the firm closed-cell grade (62–90 kPa at 25% deflection) for gaskets, flange seals and vibration pads needing higher counterforce and resistance to shifting, at 130% elongation.—213028 Shore A
SCE44/45
Specify the extra-firm closed-cell grade (90–172 kPa at 25% deflection, 0.52 density) for high-clamp flanges and load-bearing insulation or anti-vibration pads needing maximum counterforce and least creep.—211035 Shore A
Fabric / fiberglass-reinforced silicone sponge sheet
Choose for long strip gaskets, door and oven-door seals that must resist tearing and creep; fabric or glass reinforcement raises tensile strength to 6 MPa but cuts elongation to 25%.—62530 Shore A

What is Silicone Foam (Sponge Rubber) EMI-COND?

Silicone Foam (Sponge Rubber) EMI-COND is Silicone Foam (Sponge Rubber) in the EMI-COND grade — use where an enclosure joint needs environmental sealing and EMI shielding at once; Ni/C or Ag filler drops volume resistivity to the Ω·cm range, at 0.85 g/cm³ density. Silicone Foam (Sponge Rubber) EMI-COND has a tensile strength of 1 MPa (0.145 ksi), weaker than 86% of polymer grades. Elongation at break is 80% and the elastic modulus is 0 GPa (5.8×10⁻⁴ Msi). Silicone Foam (Sponge Rubber) EMI-COND has a density of 0.85 g/cm³ (0.0307 lb/in³), lighter than 83% of polymer grades. Its glass-transition temperature is -123°C (-189 °F). SCE42 is the default condition FabDigit quotes; EMI-COND is available on request or by drawing note.

Advantages

  • Good UV / weathering resistance — 95/100, better than 95% of polymer grades
  • High service temperature — 180°C (356 °F), better than 85% of polymer grades
  • Lightweight — 0.85 g/cm³ (0.0307 lb/in³), better than 83% of polymer grades
  • Forms and bends easily — 80/100, better than 75% of polymer grades

Limitations

  • Low stiffness — 0 GPa (5.8×10⁻⁴ Msi), worse than 91% of polymer grades
  • Absorbs moisture — dry before molding — 1.5%, worse than 91% of polymer grades
  • High mold shrinkage — 2%, worse than 81% of polymer grades
  • Needs corrosion protection — 70/100, worse than 78% of polymer grades

Silicone Foam (Sponge Rubber) EMI-COND properties

Typical room-temperature values for Silicone Foam (Sponge Rubber) EMI-COND; 17 are specific to this condition. Other listed values are Silicone Foam (Sponge Rubber) reference data and may not represent this condition. Bars are the position among polymer grades.

Physical3

Silicone Foam (Sponge Rubber) EMI-COND has a density of 0.85 g/cm³ (0.0307 lb/in³), lighter than 83% of polymer grades. Its glass-transition temperature is -123°C (-189 °F).

Density0.85 g/cm³0.03 lb/in³
Glass Transition (Tg)-123°C-189 °F
Water Absorption (24 h)1.5%

Mechanical8

Silicone Foam (Sponge Rubber) EMI-COND has a tensile strength of 1 MPa (0.145 ksi), weaker than 86% of polymer grades. Elongation at break is 80% and the elastic modulus is 0 GPa (5.8×10⁻⁴ Msi).

Elastic (Young's) Modulus0 GPa5.8×10⁻⁴ Msi
Poisson's Ratio0.3
Tensile Strength (Ultimate)1 MPa0.15 ksi
Elongation at Break80%
Compressive Strength0.09 MPa0.01 ksi
Hardness, Shore A45 Shore A
Tear Strength2 kN/m8.6 lbf/in
Compression Set (22 h, 70 °C)12%

Thermal8

Silicone Foam (Sponge Rubber) EMI-COND is rated for continuous service to 180°C (356 °F). It conducts heat at 0.25 W/m·K (0.144 BTU/hr·ft·°F), better than 72% of polymer grades. Thermal expansion is 250 µm/m·K (138.9 µin/in·°F).

Thermal Conductivity0.25 W/m·K0.14 BTU/hr·ft·°F
Specific Heat Capacity1,300 J/kg·K0.31 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)250 µm/m·K139 µin/in·°F
Max Service Temperature (continuous)180°C356 °F
Min Service Temperature-55°C-67 °F
Flammability (UL 94)HF-1 / V-0 achievable in FR grades; base silicone foam typically HBF–HF-1
Limiting Oxygen Index30%
Max Service Temperature (short-term)260°C500 °F

Electrical5

Silicone Foam (Sponge Rubber) EMI-COND is an electrical insulator with a dielectric strength of 5 kV/mm (127 V/mil) and a resistivity of 0.005 Ω·m.

Electrical Resistivity0.005 Ω·m196,850 µΩ·in
Dielectric Strength5 kV/mm127 V/mil
Dielectric Constant (1 MHz)1.6
Dissipation Factor (1 MHz)0.005
Volume Resistivity0.5 Ω·cm

Chemical & Environmental3

Corrosion resistance is very good (70/100), worse than 78% of polymer grades. UV resistance is excellent.

Corrosion ResistanceVery good70/100
UV / Weathering ResistanceExcellent95/100
Chemical Resistance Summary—

Sustainability4

Producing a kilogram of Silicone Foam (Sponge Rubber) EMI-COND takes about 130 MJ of energy and emits 6.5 kg of CO₂ — more than 77% of polymer grades. Typical recycled content is 0%.

Embodied Energy (primary production)130 MJ/kg55,890 BTU/lb
Embodied Carbon (primary production)6.5 kg CO₂/kg
Embodied Water250 L/kg30 gal/lb
Typical Recycled Content0%

Manufacturability4

Silicone Foam (Sponge Rubber) EMI-COND's machinability is very good (70/100, better than 74% of polymer grades); formability very good (80/100).

MachinabilityVery good70/100
Formability (cold)Very good80/100
Mold Shrinkage2%
Mold Temperature (typ.)170°C338 °F

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

Working with Silicone Foam (Sponge Rubber) EMI-COND

Is Silicone Foam (Sponge Rubber) easy to machine?

Die cutting, waterjet, CNC oscillating knife and rotary die cutting are the practical methods; turning and milling are not suitable. Back the sheet with a cutting board and use sharp edges to avoid torn edges and stretch distortion.

Can Silicone Foam (Sponge Rubber) be welded?

Not heat weldable; join with silicone-specific adhesives such as self-fusing silicone tape or platinum/condensation-cure silicone, or mold butt-spliced closed loops.

Can Silicone Foam (Sponge Rubber) be formed, bent or molded?

The usual route is calendering followed by compression molding with blowing and vulcanization at 150-200 °C, then a 200 °C post-cure to remove volatiles; sponge cord and tube can also be extruded. Design closed-cell thickness tolerance at about ±10%.

What surface finishes work on Silicone Foam (Sponge Rubber)?

Plasma or primer treatment allows PSA lamination; plating and painting are not possible, so pigment the raw compound for colour. Avoid sulfur- or amine-bearing mould releases, which inhibit platinum cure.

Silicone Foam (Sponge Rubber) 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
fumed / precipitated silica (reinforcingreinforcing filler15 – 3525
blowing agent (ADC/ OBSH) or expandable chemical blowing agent or thermally expandable microspheres1 – 63
peroxide or Pt-complex curing systemperoxide or platinum catalyst0.3 – 2.51.2
process aids / pigments / heat stabilizeprocess aids, color pastes, heat-resistance additives0.5 – 83
flame-retardant / functional filler (Pt-added in flame-retardant, thermally or electrically conductive grades0 – 400
polydimethylsiloxane (VMQ) base polymermethyl vinyl silicone rubber base gum≥ 45 (balance)—

Silicone Foam (Sponge Rubber) EMI-COND — frequently asked

What is Silicone Foam (Sponge Rubber) EMI-COND used for?

Silicone Foam (Sponge Rubber) EMI-COND is typically used for high-temperature gaskets and seals, EMI shielding gasket backing, aerospace door/duct seals and vibration dampening pads. In short: widest temperature range foam; low compression set; aerospace-qualified sponge.

What is the tensile strength of Silicone Foam (Sponge Rubber) EMI-COND?

Silicone Foam (Sponge Rubber) EMI-COND has a typical tensile strength of 1 MPa (0.145 ksi) — weaker than 86% of polymer grades. Strength varies by condition: see the 9 listed tempers.

Is Silicone Foam (Sponge Rubber) EMI-COND easy to machine?

Yes — machinability is rated very good (70/100, better than 74% of polymer grades). Die cutting, waterjet, CNC oscillating knife and rotary die cutting are the practical methods; turning and milling are not suitable. Back the sheet with a cutting board and use sharp edges to avoid torn edges and stretch distortion.

Can Silicone Foam (Sponge Rubber) EMI-COND be welded?

Not heat weldable; join with silicone-specific adhesives such as self-fusing silicone tape or platinum/condensation-cure silicone, or mold butt-spliced closed loops.

What surface finishes work on Silicone Foam (Sponge Rubber) EMI-COND?

Plasma or primer treatment allows PSA lamination; plating and painting are not possible, so pigment the raw compound for colour. Avoid sulfur- or amine-bearing mould releases, which inhibit platinum cure.

Can Silicone Foam (Sponge Rubber) EMI-COND be formed, bent or molded?

The usual route is calendering followed by compression molding with blowing and vulcanization at 150-200 °C, then a 200 °C post-cure to remove volatiles; sponge cord and tube can also be extruded. Design closed-cell thickness tolerance at about ±10%.

What is the maximum service temperature of Silicone Foam (Sponge Rubber) EMI-COND?

Silicone Foam (Sponge Rubber) EMI-COND is rated for continuous use to about 180°C (356 °F), and briefly to 260°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Sources

  1. ASTM D1056 — Standard Specification for Flexible Cellular Materials, Sponge or Expanded Rubber — ASTM International (2020)
  2. ASTM D3574 / D395 — cellular material compression set and deflection test methods — ASTM International (2017)
  3. AMS 3195 — Silicone Rubber Sponge, Low-Temperature Resistant — SAE International (2019)
  4. BISCO HT-800/HT-820/HT-870 silicone foam data sheets — Rogers Corporation (2023)
  5. Silicone sponge and foam gasket material technical data — Stockwell Elastomerics (2023)
  6. Engineered Materials Handbook, Vol. 2: Engineering Plastics / elastomer data — ASM International (1988)

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.