Using Polyester Fibers for Improving Acoustics and Saving Weight in Automotive Applications 2001-01-1457

With today's push towards quieter and more fuel-efficient vehicles, the automotive industry must seek alternative materials for use in applications where the same material technology has been used for many years. Polyester fibers offer an excellent option as a material alternative to address the needs of this industry now and in the future. Polyester fibers can provide improved acoustics and lighter weight in many of the same applications as traditional decouplers and absorbers such as foam, cotton fiber (shoddy), and fiberglass. When designed properly, the polyester insulator/absorber can be used in underhood applications such as hood absorbers, engine side dash insulators, tunnel insulators, trim panel absorbers, watershields, headliner absorption, underpads, and dash insulators, to name a few.

The purpose of this paper is to demonstrate the superior effectiveness of polyester products over traditional insulators. The test results indicated overall improved acoustics and as much as a 30% weight savings, in some tests. Testing was completed by replacing the current production underpad, hood insulator, trim absorption, and dash insulator decoupler with the same thickness and lighter density polyester fiber to demonstrate that equal or better acoustical performance could be attained at a lighter weight. In some cases an improvement of 2 dBA resulted with a 5-7% Articulation Index improvement. In all cases, the polyester fiber performed the same or better than the current production parts.

The advantages of using polyester fibers in today's market are that in the proper application, they are lighter, recyclable, cost competitive, and better acoustically than foams, cotton shoddy, and fiberglass.