Polyphthalamide – a high-performance hybrid material

What is polyphthalamide (PPA)?

Polyphthalamide (PPA) is a high-temperature-resistant, semi-crystalline, high-performance plastic from the polyamide group. Compared to standard polyamides such as PA6 or PA66, PPA offers significantly higher thermal and chemical stability, better dimensional stability, and lower moisture absorption. This makes the material ideal for technical components in demanding environments – for example, in the automotive, electrical, or mechanical engineering sectors – as well as for carrier components in Plastic composite parts, where PPA is used thanks to its direct adhesion to elastomers without additional adhesion promoters for media-resistant sealing systems and high-temperature applications.

 

Polyphthalamide (PPA) has the following properties: * **High thermal stability**: PPA can withstand high temperatures without significant degradation, making it suitable for under-the-hood automotive applications and electrical components. * **Excellent mechanical strength**: It exhibits high tensile strength, stiffness, and impact resistance, even at elevated temperatures. * **Good chemical resistance**: PPA is resistant to a wide range of chemicals, including oils, greases, fuels, and many solvents. * **Low moisture absorption**: Compared to other polyamides, PPA absorbs less moisture, which contributes to better dimensional stability and maintained mechanical properties in humid environments. * **Good electrical insulation properties**: PPA is an excellent electrical insulator, making it useful in electrical and electronic applications. * **Dimensional stability**: Due to its low moisture absorption and high stiffness, PPA parts maintain their shape and size well under varying conditions. * **Good processability**: PPA can be processed using standard injection moulding techniques, although it requires higher processing temperatures than traditional polyamides. * **Wear resistance**: PPA offers good resistance to abrasion and wear.

PPA is particularly stable against continuous thermal load (up to approx. +150°C, briefly up to +250°C), offers high rigidity, Strength and excellent creep resistance. It retains its shape even with thin-walled structures and under load - even at elevated temperatures and humidity.

 

Further advantages:

  • Very low water absorption, therefore high dimensional stability
  • Excellent chemical resistance to Oiling, fuels, coolants, esters and many solvents
  • High dimensional stability even with temperature changes
  • Good flame resistance (achievable with UL94 V-0 additives)
  • Can be reinforced with glass fibres, minerals or carbon fibres

 

In contrast to PA PPA is able to fulfil structural-mechanical requirements at high temperatures with high precision - which is why it is often used as a metal substitute in lightweight constructions.

 

Where is polyphthalamide (PPA) applied?

PPA is found in highly stressed technical components such as:

  • Pump housings, valve blocks, sensor housings
  • Fuel systems in automotive engineering (e.g. connectors, components in contact with media)
  • Rubber-plastic composite parts with elastomers for media-resistant Sealing systems
  • Connectors, coilformers and insulating parts in electronics
  • Spare parts for metal applications, e.g. for corrosive or weight-relevant requirements

 

In combination with thermoplastic elastomers The result is a high-performance hybrid material that can also be used for Multi-component injection moulding can be used. Adhesion promoters are required for other elastomers.