High-temperature insulation demands materials that do not compromise under thermal cycling, electrical stress, or chemical exposure. Polyimide sheet for high temperature insulation is engineered to address these challenges in semiconductor fabrication, power generation, and flexible circuit assembly. As a certified polyimide sheet manufacturer, we provide rolled and skived sheet with thickness tolerances down to ±0.005 mm. The material works equally well as a polyimide plate heat resistant option for press pads and thermal barriers, and as a PI sheet for semiconductor wafer handling and test fixtures where low outgassing is critical. In addition, our film is supplied for circuit builders as a PI sheet for flexible printed circuit substrates with superior dimensional stability.
The Polyimide Sheet for High Temperature Insulation is a thermoset polyimide product that maintains dielectric and mechanical integrity from -269°C to 400°C. It is produced through high-pressure curing of polyamic acid resin, resulting in a dense, void-free structure with excellent resistance to hydrolysis, ionizing radiation, and industrial solvents. Unlike many organic polymers, this sheet does not melt or drip when exposed to flame; it chars at temperatures above 500°C while retaining its insulating properties. Typical applications include slot liners in high-speed traction motors, coil separators, transformer layer insulation, vacuum furnace linings, and heat-resistant gaskets for exhaust systems.
To support engineering selection, the following key performance characteristics are provided for standard sheet thicknesses from 0.025 mm to 6.35 mm:
Detailed values for a standard 0.125 mm (5 mil) sheet are shown below:
| Parameter | Typical Value | Test Method |
|---|---|---|
| Thickness | 0.125 mm ± 0.008 mm | ASTM D374 |
| Width | Up to 1000 mm | Laser micrometer |
| Density | 1.42 g/cm³ | ASTM D792 |
| Tensile strength (MD) | 231 MPa | ASTM D882 |
| Elongation at break (MD) | 72% | ASTM D882 |
| Dielectric strength | 118 kV/mm | ASTM D149 |
| Volume resistivity | 1.6 × 10^17 Ω·cm | ASTM D257 |
| Dielectric constant (1 MHz) | 3.4 | ASTM D150 |
| Dissipation factor (1 MHz) | 0.002 | ASTM D150 |
| Continuous operating temperature | -269°C to 400°C | Thermal cycling, 1000 h |
| Short-term peak temperature | 480°C | Internal test |
| Flammability | UL94 V-0 | UL 94 |
| Water absorption (24 h) | 0.8% | ASTM D570 |
| Thermal conductivity | 0.12 W/m·K | ASTM E1530 |
| Outgassing (TML / CVCM) | 0.08% / 0.02% | ASTM E595 |
