Table of Contents
Fundamentals and properties of polyphenylene sulphide (PPS)
Polyphenylene sulfide (PPS) is a partially aromatic, semi-crystalline polymer with a unique structure of benzene rings linked by sulfur atoms (Aoki et al., 2023). This special molecular architecture gives the material extraordinary properties that make it one of the most important high-performance plastics in modern industry.
The crystallinity of PPS plays a decisive role in its performance. Typical degrees of crystallinity are between 30-50%, depending on processing, fillers and additives (Aoki et al., 2023). This crystalline structure is significantly influenced by the cooling rate after processing:
- Slow cooling leads to higher crystallinity crystallinity with increased stiffness and modulus of elasticity
- Rapid cooling increases ductility and changes fracture behavior
- The crystallinity directly determines the mechanical and thermal properties
- Higher crystallinity results in improved heat resistance and greater thermal stability. thermal stability
PPS has a high melting point of around 280-285 °C, making it suitable for applications where high temperatures can occur in the short term (SpecialChem, 2024). The glass transition temperature is around 85-88 °C (Aoki et al., 2023). This range means that PPS is hard and dimensionally stable at room temperature, but becomes increasingly elastic above the glass transition temperature. Depending on the application, this can be both advantageous and limiting: PPS is less suitable for components that are permanently in contact with hot media – such as water or steam – while it proves its worth in electrical, mechanical and chemically stressed environments thanks to its high dimensional stability and thermal resistance.
Thermal stability and temperature resistance
The thermal stability of PPS is one of its most important unique selling points and makes it a preferred material for high-temperature applications. PPS remains structurally and mechanically stable up to 220-240 °C in continuous operation, while short-term loads of up to 260-280 °C can be withstood without damage (Aoki et al., 2023).
The excellent temperature resistance offers several decisive advantages:
- Long-term load capacity over many thousands of hours at temperatures up to 230 °C without significant deterioration in properties
- Dimensional stability due to low thermal expansion and high dimensional stability
- Less material fatigue thanks to high thermal ageing stability
- Minimized risk of embrittlement, cracking or creep over the life cycle
The material only begins to decompose at around 490 °C, which offers an enormous margin of safety for practical applications (Aoki et al., 2023). This exceptional temperature stability allows PPS to be used in extreme areas where other plastics would fail.
Chemical resistance and material diversity
PPS offers excellent resistance to chemically aggressive substances such as acids, alkalis, solvents and oxidizing media – even at temperatures of over 200 °C (Aoki et al., 2023). The plastic is largely inert to UV radiation and has a very low water absorption of less than 0.1 percent, which clearly underlines its dimensional and dimensional stability even under extreme environmental conditions.
In addition to homopolymer PPS, there are numerous variants that are specifically tailored to special requirements. These include copolymers with additional aromatic or sulfone-containing units as well as glass fiber-reinforced PPS compounds, which enable a particularly high mechanical load-bearing capacity. Carbon or mineral fibers are also used for tribological applications, while PPS fiber membranes are used in special filter processes. Commercial grades with different degrees of purity and varying filler content are also available.
The mechanical load-bearing capacity can be significantly increased by using fillers, with glass fiber-reinforced PPS being the standard for highly stressed components (Aoki et al., 2023). PPS is also characterized by its natural fire resistance in accordance with UL94 V-0 and very good electrical insulation properties.
Industrial applications and areas of use
The most important industrial applications for PPS are in areas where excellent thermal, chemical and mechanical resistance is required (MaxNext, 2024). The versatility of the material is reflected in its wide range of applications:
Electronics and electrical engineering:
- Insulators, housings, printed circuit boards and connectors
- High-voltage applications thanks to electrical insulation properties
- Secure packaging for sensitive electronic components
Automotive industry:
- Engine components, fuel systems, lamp sockets
- Thermostats, sensor and connection parts and bearings
- Ensuring reliability and durability under extreme conditions
Chemical industry and processing:
- Valves, pump housings, fittings and filter housings for corrosive media
- Durable and drop-resistant components in chemical production technology
Medical technology applications benefit from the high biocompatibility, sterilizability and resistance to disinfectants (MaxNext, 2024). In the aerospace industry, PPS components are valued for their reliability under extreme environmental conditions.
Current developments and innovations
New developments in PPS focus on special compounds, innovative manufacturing processes and material modifications for lightweight construction and electromobility (Kunststoff-Magazin, 2024). Modern PPS compounds contain reinforcing additives such as glass fibers up to 40% or minerals, which further improve strength, creep resistance and stability at high continuous operating temperatures.
Important development trends:
- Optimization for e-mobility with better compatibility with ultra-low viscosity automatic transmission oils
- Blow molding and lightweight construction innovations for complex charge air ducts and air intake modules
- Sustainability and improved recyclability thanks to chlorine-free, environmentally friendly compounds
- Cost savings through manufacturing innovation and functional integration
Manufacturers are specifically developing PPS solutions for components in electric gearboxes, battery seals and sensors, which are essential for electric vehicles (Kunststoff-Magazin, 2024). The combination with innovative design methods enables up to 25% reduction in production costs with maximum design freedom and low weight.
Conclusion
PPS is establishing itself as an indispensable high-performance plastic for demanding industrial applications thanks to its unique combination of
thermal stability
chemical resistance and mechanical strength. Its exceptional temperature resistance up to around 240 °C, outstanding dimensional stability and natural flame retardancy make PPS the material of choice for extreme applications in the
automotive
and chemical industries.
At the same time, it should be noted that PPS also has disadvantages despite its outstanding properties. These include the comparatively high manufacturing costs and the limited recycling properties – the material is hardly degradable and is difficult to recycle, which poses ecological challenges. In addition, PPS is usually dark in color (often black) and therefore only available in limited color variants.
Nevertheless, the continuous further development of PPS compounds and their adaptation to future-oriented technologies such as electromobility underline the strategic importance of this versatile material. With its excellent cost-benefit ratio in industrial applications and its outstanding processing properties, PPS will continue to play an important role in modern materials technology in the future.
Bibliography
Aoki et al. (2023) The history, interests and future of polyphenylene sulfide (PPS). High Performance Polymers, 35(10), 1060-1078.
Available at: https://journals.sagepub.com/doi/10.1177/09540083231212148 (Accessed: September 18, 2025).
Kunststoff-Magazin (2024) Thermoplastics – Plastics for vehicle construction. Available at: https://www.kunststoff-magazin.de/thermoplaste/thermoplaste—kunststoffe-fuer-den-fahrzeugbau.htm (Accessed: September 18, 2025).
Martan Plastics (2024) Polyphenylene sulfide – Materials. Available at: https://martanplastics.com/werkstoffe/polyphenylensulfid/ (Accessed: September 18, 2025).
MaxNext (2024) Polyphenylene sulfide (PPS) – Applications and advantages. Available at: https://maxnext.io/de/blog/meta-titel-polyphenylensulfid-pps-anwendungen-vorteile/ (Accessed: September 18, 2025).
Meviy (2024) PPS Material Guide. Available at: https://de.meviy.misumi-ec.com/info/de/blog-de/materials-de/29521/ (Accessed: September 18, 2025).
SpecialChem (2024) Polyphenylene Sulfide (PPS) Plastic Guide. Available at: https://www.specialchem.com/plastics/guide/polyphenylene-sulfide-pps-plastic-guide (Accessed: September 18, 2025).
