Manufacturing of Lightweight Sandwich Foam with Optimized Bending Properties for Interior Aircraft Application

Abstract

Thermoplastic foams, made from polyetherimide (PEI) for example, combine low densities with excellent flame retardant properties. Therefore, they provide an excellent choice for interior application in commercial aircrafts. However, reduced densities cause low mechanical properties. Structural foams have a sandwich-like structure with a dense surface and low-density foam core. They show increased mechanical properties compared to thermoplastic foams and low part weights compared to solid parts. Thermoplastic foams can be transformed into structural foams by using hot press processes. In such a process, polymer skins are produced on the foam surface through compaction of foam cells at temperatures above glass transition temperature of the amorphous polymer. This paper will present a new process to manufacture structural foams from thermoplastic foams and investigate the effect of this transformation on mechanical properties.