Quick answer: PEEK and PPS are engineering plastics for demanding conditions, but they are not selected for the same reason. PEEK is usually justified when an application combines high temperature, mechanical load, wear, and aggressive chemicals. PPS is a strong alternative when chemical resistance, dimensional stability, and good service temperature are needed with a more efficiency-focused technical selection.
What are PEEK and PPS?
PEEK stands for polyether ether ketone. It is a high-performance thermoplastic used when materials such as POM, PA, or PC no longer meet the required thermal, chemical, or mechanical level.
PPS stands for polyphenylene sulfide. It is an engineering polymer known for chemical resistance, dimensional stability, and performance in demanding thermal environments. In many applications, PPS can cover needs that require more performance than standard plastics without always reaching the extreme technical level of PEEK.
Comparison table: PPS vs PEEK
| Criterion | PEEK | PPS |
|---|---|---|
| Temperature | Very high, for critical applications | High, suitable for many industrial applications |
| Chemical resistance | Excellent | Excellent against many industrial chemicals |
| Wear and friction | Very good performance, especially in suitable grades | Good, depending on load and formulation |
| Dimensional stiffness | High | High, especially in reinforced grades |
| Typical application | Aerospace, medical, critical chemical, high temperature | Electrical, automotive, chemical, dimensional components |
| Practical selection | When failure is not acceptable and the requirement demands it | When high performance is needed with an efficiency focus |
When to choose PEEK
Choose PEEK when the part operates with high temperature, pressure, mechanical load, or severe chemical exposure. It is also useful when the component must keep dimensional stability through repeated cycles or when performance is required in medical, aerospace, energy, or advanced manufacturing applications.
PEEK can also be a good option when replacing metal in parts where weight, corrosion, electrical insulation, or wear are critical factors.
When to choose PPS
Choose PPS when you need chemical resistance, stiffness, and stability at elevated temperature, but the application does not necessarily require PEEK’s maximum performance level. In electrical components, automotive parts, supports, insulators, and precision technical parts, PPS can be a highly competitive solution.
Reinforced grades, such as glass-filled PPS, can improve stiffness, dimensional stability, and structural capability. This makes PPS useful for parts where geometry must remain stable under load and temperature.
Criteria for choosing between PPS and PEEK
1. Real temperature, not just maximum temperature
Define whether the part sees continuous temperature, occasional peaks, or thermal cycling. A single maximum temperature does not always justify PEEK. If exposure is moderate or intermittent, PPS may be enough.
2. Mechanical load and wear
If there is sliding contact, repeated load, or severe wear, PEEK can provide more margin. If the main function is support, insulation, or dimensional stability, PPS can be a solid option.
3. Chemicals present
Both materials resist many chemicals, but compatibility must be reviewed with the specific fluid, concentration, temperature, and exposure time. Do not select only by material family.
4. Machining and geometry
PEEK and PPS can be machined, but part geometry, tolerances, wall thicknesses, and stability after machining affect the result. For critical parts, review the drawing before choosing the grade.
Common mistakes
- Using PEEK when PPS covers the technical need.
- Using PPS when the application requires extreme wear, load, or temperature performance.
- Comparing only maximum temperature and forgetting chemicals, load, and tolerances.
- Not defining whether the part will be molded, extruded, or machined from plate or rod.
- Ignoring reinforced or ESD grades when the application requires them.
Request a technical comparison
To choose between PEEK and PPS, share operating temperature, chemicals, load, tolerances, drawing, and part function. PomDepot can help compare PEEK, PPS, and reinforced PPS to avoid over- or under-specifying the material.
FAQs
Can PPS replace PEEK?
It can replace PEEK in some applications where temperature, load, and wear do not require PEEK’s maximum performance. It should not be assumed equivalent without reviewing operating conditions.
Is PEEK always better than PPS?
Not necessarily. PEEK offers more technical margin in critical applications, but PPS may be more appropriate when the main requirement is dimensional stability and chemical resistance in less extreme conditions.
What is glass-filled PPS used for?
Glass-filled PPS improves stiffness, dimensional stability, and structural capability, especially in parts under load or temperature.