Compression behavior of warp-knitted spacer fabrics for cushioning applications

TLDR

Cushioning materials absorb kinetic energy under compression at a relatively constant stress over a large displacement range, but conventional polyurethane foams have poor moisture transmission, whereas warp‑knitted spacer fabrics offer comparable cushioning with superior moisture permeability when structural parameters are optimized. This study investigates the compression behavior of warp‑knitted spacer fabrics designed for cushioning applications. The fabrics were produced on a double‑needle bar warp‑knitting machine (gauge 18) by varying spacer yarn inclination, fineness, thickness, and outer‑layer structure, and their compression stress‑strain curves and energy‑efficiency diagrams were analyzed to assess the effect of each parameter. Warp‑knitted spacer fabrics proved to be ideal energy absorbers for cushioning, with their absorption capacity easily tailored to specific requirements by adjusting structural parameters guided by efficiency diagrams.

Abstract

Cushioning materials generally absorb kinetic mechanical energy under compression actions at a relatively constant stress over a large range of displacement. However, cushioning materials widely used today are polyurethane (PU) foams with low moisture transmission. As a new class of three-dimensional textile structures, warp-knitted spacer fabrics not only have much better moisture transmission property than PU foams, but also have the similar cushioning performance if appropriate structural parameters are adopted. This paper reports an experimental study on the compression behavior of a series of warp-knitted fabrics made for cushioning applications. These fabrics were produced on a double-needle bar warp knitting machine of gauge 18 by varying different structural parameters including spacer yarn inclination angle and fineness, fabric thickness, and outer layer structure. Both the compression stress-strain curves and energy efficiency diagrams from the testing results were used to analyze the compression behavior of these fabrics and the effect of each structural parameter. The results indicate that warp-knitted spacer fabrics are an ideal class of the energy absorbers for cushioning applications and their energy-absorption capacity can easily be tailored to meet specific end-use requirements by simply varying their structural parameters with the help of efficiency diagrams.