For severe applications requiring repeated sterilization or uncompromising toughness, Polyphenylsulfone(PES) really stands out. With its high heat deflection temperature of 218°C, it can withstand continuous exposure to heat and still absorb tremendous impact without deflecting or breaking. Plus its chemical resistance surpasses that of most amorphous polymers. While more expensive than other sulfone polymers, It earns its reputation as a prize fighter.