Compression and vibration behavior of foams, knitted spacers and nonwoven spacers: An experimental study

Abstract

PU-foams, either used alone or lined with a mesh fabric, are widely employed in the automotive and packaging industries for cushioning and insulation applications. In response to ecological challenges, this study explores and compares the characteristics of three different types of materials: traditional PU foams, warp-knitted spacers and a nonwoven sandwich structure called Vertilap®. Previous studies on Vertilap® are focused on its compression behavior meanwhile the present work examines and compares the vibration damping properties of all three materials. Spacer fabrics, made from either knitted textiles or nonwoven pleats, can be produced from a single material, which increases their recyclability. To determine the potential of these materials to serve as foam substitutes, their performance under quasi-static compression and vibration is compared. These properties are a reliable indicator of the comfort level of the materials. The results reveal that Vertilap® and knitted spacers have a comparable behavior under vibration and a lower isolation frequency compared to the analyzed foams, with comparable transmissibility depending on the stiffness. Furthermore, Vertilap® tends to dissipate more energy during static compression due to friction between its nonwoven layers; it can also withstand similar loads at 25 and 50% deformation rates as the other materials.