Extreme High-Temperature Grade Silicone Sheeting
Extreme High-Temperature Grade Silicone Sheeting is a solid silicone elastomer formulated with advanced heat stabilizer technology to exceed the thermal performance of standard general-purpose silicone, with an operating range of -85°F to +600°F (intermittent). Available in 55 and 60 Shore A durometer grades, the material delivers high tensile strength, elongation, and tear resistance maintained after extended heat aging — greater than 750 psi tensile, greater than 90% elongation, and greater than 70 ppi tear after 168 hours at 300°C.
Key Properties
- Durometer, Shore “A”: 60 ±5 (60 Duro) / 55 ±5 (55 Duro) — ASTM D2240
- Tensile Strength, psi: 1200 (60 Duro) / 1050 (55 Duro) — ASTM D412
- Elongation, %: 450 / 450 — ASTM D412
- Tear, ppi Die “B”: 140 (60 Duro) / 130 (55 Duro) — ASTM D624
- Specific Gravity, g/cc: 1.27 (60 Duro) / 1.25 (55 Duro) — ASTM D297
- Service Temperature: -85°F to +600°F (intermittent)
We want to help!
Enter your information and we'll get you in touch with our knowledgable staff. We know how important to the right product for your project.
Request a Consultation
- Specifications
- Applications
- General Info
- FAQs
Physical Properties
| Property | Value | Test Method |
| Specific Gravity, g/cc — 60 Duro | 1.27 | ASTM D297 |
| Specific Gravity, g/cc — 55 Duro | 1.25 | ASTM D297 |
| Durometer, Shore “A” — 60 Duro | 60 ±5 | ASTM D2240 |
| Durometer, Shore “A” — 55 Duro | 55 ±5 | ASTM D2240 |
| Tensile Strength, psi — 60 Duro | 1200 | ASTM D412 |
| Tensile Strength, psi — 55 Duro | 1050 | ASTM D412 |
| Elongation, % — 60 Duro | 450 | ASTM D412 |
| Elongation, % — 55 Duro | 450 | ASTM D412 |
| Tear, ppi Die “B” — 60 Duro | 140 | ASTM D624 |
| Tear, ppi Die “B” — 55 Duro | 130 | ASTM D624 |
Aging Performance — Heat Aging (168 hrs @ 300°C, All Grades)
| Property | Value | Test Method |
| Tensile Strength, psi (retained) | >750 | — |
| Elongation, % (retained) | >90 | — |
| Tear, ppi Die “B” (retained) | >70 | — |
- High-temperature industrial seals and gaskets in sustained elevated-temperature service
- Aerospace and aviation thermal barrier components exposed to exhaust or engine proximity heat
- Exhaust system sealing and insulation requiring long-term thermal stability
- Electrical insulation components in elevated-temperature enclosures and assemblies
- Die-cut gasketing for heat-critical assemblies where standard silicone grades are insufficient
Common industries: Aerospace, aviation, industrial manufacturing, power generation, automotive.
Extreme High-Temperature Grade Silicone Sheeting is a solid silicone elastomer product line engineered for sealing and insulation applications where thermal exposure exceeds the limits of standard general-purpose silicone. The formulation incorporates advanced heat stabilizer technology that extends the continuous service ceiling to +600°F (intermittent) while maintaining the broad low-temperature capability of -85°F standard to silicone elastomers.
Available in 55 Shore A and 60 Shore A durometer grades, the material is easily die-cut and supplied in thicknesses from .010″ to .500″ and widths up to 60″, with various color and catalyst options.
A defining characteristic of Extreme High-Temperature Grade Silicone Sheeting is its retention of mechanical performance under prolonged heat exposure. After 168 hours at 300°C, the material retains greater than 750 psi tensile strength, greater than 90% elongation, and greater than 70 ppi tear resistance — performance thresholds that standard silicone grades do not meet under equivalent aging conditions. The cured sheet is non-toxic and chemically inert, fabricated from high-quality certified raw materials, and resistant to UV and ozone degradation.
What differentiates Extreme High-Temperature Grade Silicone Sheeting from standard general-purpose silicone sheeting?
Extreme High-Temperature Grade Silicone Sheeting is formulated with advanced heat stabilizer technology that extends the upper service limit to +600°F (intermittent) — significantly higher than general-purpose silicone grades. Its key differentiator is documented mechanical property retention after 168 hours at 300°C: greater than 750 psi tensile, greater than 90% elongation, and greater than 70 ppi tear. Standard silicone grades do not carry equivalent heat-aged performance data at these conditions.
Why does heat-aged mechanical performance matter for silicone sheeting selection?
Silicone elastomers can degrade under sustained high-temperature exposure, losing tensile strength, elongation, and tear resistance over time — which can lead to seal failure, compression set buildup, or cracking in service. Extreme High-Temperature Grade Silicone Sheeting's heat aging data (168 hrs at 300°C) provides engineers with documented assurance that the material retains functional mechanical properties after extended thermal exposure, not just at initial installation.
What is the operating temperature range for Extreme High-Temperature Grade Silicone Sheeting?
-85°F to +600°F (intermittent), as listed on the TDS.
Is Extreme High-Temperature Grade Silicone Sheeting suitable for aerospace applications?
Extreme High-Temperature Grade Silicone Sheeting is used in aerospace and aviation thermal barrier and sealing applications based on its temperature performance and certified raw material construction. However, no specific aerospace qualification standards (such as AMS or MIL specs) are listed on the manufacturer's TDS. Consult H-O Products regarding application-specific qualification requirements.
How should Extreme High-Temperature Grade Silicone Sheeting be specified?
Specify Extreme High-Temperature Grade Silicone Sheeting, durometer (55 Shore A or 60 Shore A), thickness, color and catalyst options as required, dimensional tolerances, and finished format.
