Green Matter: Arkema wins Pierre Potier prize – again

Touted as a ground-breaking metal-replacement innovation, Rilsan HT is said to be six times lighter than steel and three times lighter than aluminum. Its high temperature resistance makes it suitable for under-the-hood tubing applications, says Arkema.

The result of ongoing research at Arkema’s Cedato center in Normandy, France, the high-temperature biopolymer is made from the seeds of the inedible castor bean and, in the first instance, was developed with carmakers in mind. For decades Arkema has been developing its expertise in polyamide 11, a lightweight, flexible nylon, with excellent chemical and thermal (up to 150°C) stability properties. Yet to comply with the latest developments in the environmental legislation and regulations, this was not enough.

As Estelle Pierrat, a development engineer at Arkema, explains in the video about this material, the increasingly stringent environmental standards on vehicle emissions (including CO2) have meant that carmakers have worked steadily to reduce vehicle weight, which has led them to thoroughly redesign the combustion engine. The result: the emergence of new, lighter fluid transfer systems designed to improve engine yields and new temperature specifications due to the higher temperatures that are generated under the hood.

The polyamides available to date for flexible tubing manufacture were, however, unable to withstand these higher temperatures, which reached 150°C, and more, while traditional solutions based on metal or metal-rubber assemblies had the disadvantage of being heavy, and often costly and difficult to process. A new polymer combining the high temperature stability of metal and rubber with the flexibility and lighter weight of polyamides was clearly required. This led Arkema to invest in the development of an extrudable, flexible polyphthalamide (PPA) capable of withstanding high temperatures and aggressive fluids.

Rilsan HT is the first PPA to meet all these requirements. This newest PPA, according to Pierrat, “can accommodate a further 30°C in operating temperature.” The material is easy and economical to process using all conventional processing technologies, offers high design freedom and is said to reduce overall manufacturing costs while meeting the lifetime requirements of automotive parts.

At Arkema, applications outside the automotive industry are also envisioned. Oil exploration and the aerospace industry are examples of promising areas that could benefit from the advantages offered by this PPA.