Toray PPS (polyphenylene sulfide) films and molding compounds are increasingly used in electrical insulation. Their unique molecular structure delivers multiple protective properties, meeting industrial needs for heat resistance, flame retardancy, dimensional stability, and chemical resistance. Below is an overview of its performance and applications to help equipment manufacturers quickly identify its value.

1. Heat Resistance: Wide Long-Term Operating Temperature Range

PPS’s main chain includes rigid benzene rings and thioether bonds, giving it a much higher thermal decomposition onset than common engineering plastics. In heat-generating equipment like dry-type transformers, traction motors, and PV inverters, Toray PPS insulation maintains dielectric strength and mechanical toughness in high-temperature areas. This reduces thermal aging-related cracking and chalking, extending maintenance intervals.

2. Flame Retardancy: Halogen-Free & Self-Extinguishing for Safety

PPS resin has a high oxygen index. When exposed to flame, a carbonized layer quickly forms to block oxygen and flammable gases. With special filler synergy, Toray PPS further lowers smoke density—meeting strict flame retardancy requirements for rail vehicles, charging piles, and data centers. No halogenated flame retardants are needed, avoiding secondary environmental risks.

3. Dimensional Stability: Resists Deformation in Thermal Cycles

Electrical equipment expands and contracts repeatedly due to temperature changes or load fluctuations. Traditional plastics easily creep, causing loose coils and air gap discharge. Toray PPS has a low linear thermal expansion coefficient and lower water absorption than most polymers; its post-processing dimensions are barely affected by humidity. This ensures long-term fitting precision for high-voltage coils, bus ducts, and relay frames.

4. Chemical Resistance: Withstands Oil & Cleaners

In petrochemical, offshore wind, and papermaking sectors, insulation is often exposed to oil mist, acids, alkalis, and steam. Toray PPS is inert to aliphatic hydrocarbons, halogenated solvents, and weak acids/alkalis—its surface rarely cracks or swells, maintaining interfacial insulation resistance. Industrial cleaners can be used directly during regular maintenance, no disassembly required, cutting maintenance time.

5. Electrical Performance: Low Dielectric Loss + High Breakdown Strength

Toray PPS has minimal dielectric constant and loss factor fluctuations across wide temperature/frequency ranges, making it ideal for insulation in high-frequency switching power supplies and SiC/GaN power modules. Its breakdown field strength also withstands impulse voltages, reducing partial discharge risks and providing a stable long-term insulation barrier for control systems.

6. Processability & Integration: Films, Sheets, Custom Parts

Toray supplies PPS in four key forms: films, extruded sheets, injection pellets, and fiber-reinforced prepregs—compatible with customer processes like lamination, hot pressing, ｉｎｓｅｒｔ molding, and wrapping. For space-constrained areas or custom heat dissipation channels, laser cutting and CNC finishing enable fast prototype testing and mass production.

As a Toray partner, Sui On Insulationprovides PPS film insulation products and secondary processing (roll slitting, stamping, adhesive lamination) per project needs. Our technical team understands UL, IEC, and GB standard differences, supporting structural optimization and material selection during design. After-sales engineers are based in major East/South China industrial cities to handle on-site installation and troubleshooting.