PPA
(Polyphthalamide)
PPA is a relatively new, semi-crystalline material, with an excellent cost to performance ratio. PPA bridges the performance gap between nylons/polyesters, and higher priced, high temperature materials such as PEI and PEEK.
PPA has excellent impact strength and is not notch sensitive. PPA does absorb moisture, and its properties change as a result. This change is not nearly as great as 6-6 nylon. Despite its relatively recent introduction, good design data is available for PPA.
