Some Principles of Nonwoven Fabrics1

Abstract

The authors compare the mechanical behavior of woven and nonwoven fabrics. They outline the principal mechanisms by which woven cloths deform and recover in manufacture and in end usage. They attempt to formulate a parallel sequence of events in the distortion process for nonwovens and to show how these actions influence the ability of nonwovens to fit smoothty on three-dimensionally curved surfaces, to hang and drape freely, and to recover from bends and tensile extension. Some results of a research program recently conducted at M.I.T. on nonwovens are presented. This study is related to the directional tensile behavior of nonwoven fabrics and demonstrates how knowledge of fiber properties and web structure can be used effectively to predict web behavior. Fiber behavior measured on the Instron provide the material constants necessary for insertion in derived analytical expressions , for nonwoven fabric stiffness and contraction ratios. Predicted nonwoven behavior shows reasonable agreement with experimental measurements on the particular materials studied.