Thermal stability, dimensional stability, chemical resistance and inherent flame retardancy

Ryton® PPS (polyphenylene sulfide) compounds offer a unique combination of properties and a cost/performance balance unmatched by other engineering thermoplastics:

  • Thermal Stability: A remarkable combination of both long-term resistance to temperatures up to 200°C (392°F) and short-term resistance to temperatures up to 260°C (500° F)
  • Dimensional Stability: Even complex parts could be molded with very tight tolerances and will maintain dimensional stability even at elevated temperatures and and in harsh chemical environment
  • Chemical Resistance: Resistant to a wide variety of solvents and corrosive chemicals even at elevated temperatures
  • Inherent Flame Retardancy: All Ryton® PPS compounds have UL94 V-0 flammability ratings without flame retardant additives


What is PPS?


Poly(p-phenylene sulfide) (PPS) is a polymer made up of alternating sulfur atoms and phenylene rings in a para substitution pattern. The highly stable chemical bonds of its molecular structure impart a remarkable degree of molecular stability toward both thermal degradation and chemical reactivity. The molecular structure also readily packs into a very thermally stable crystalline lattice, hence PPS is a semi-crystalline polymer with a high crystalline melting point of about 285°C (545°F). Because of its molecular structure, PPS also tends to char during combustion, making the material inherently flame retardant. PPS has not been found to dissolve in any solvent at temperatures below about 200°C (392°F).


When blended with glass fibers and other fillers, PPS produces engineering plastics having a unique combination of properties including:

  • A remarkable combination of both long-term and short-term thermal stability
  • Exceptionally high modulus and creep resistance
  • Outstanding resistance to a wide variety of aggressive chemical environments
  • Precision molding to tight tolerances with high reproducibility
  • Inherent non-flammability without flame retardant additives
  • Dielectric and insulating properties stable over a wide range of conditions