Polyphenyl ether is widely used in high-temperature environments due to its exceptional thermal stability. It serves as a heat transfer fluid in industrial processes, particularly in applications requiring consistent performance at elevated temperatures. Its low volatility and resistance to oxidation make it suitable for use in high-temperature heat exchangers and thermal management systems.

In the aerospace industry, it is utilized as a lubricant for aircraft engines and components, where it withstands extreme temperatures and reduces wear. Its ability to maintain viscosity under harsh conditions ensures reliable performance in critical systems.

Additionally, polyphenyl ether is employed in vacuum pump oils, providing efficient lubrication and sealing in vacuum systems. Its low vapor pressure and chemical inertness make it ideal for maintaining high vacuum levels in laboratory and industrial settings.

In electronics, it is used as a dielectric fluid in transformers and capacitors, offering excellent electrical insulation properties. Its stability at high temperatures ensures the longevity and reliability of electronic components.

Overall, polyphenyl ether's unique properties make it a valuable material in industries requiring high thermal and chemical stability.