Studies on nature of anisotropy of tensile properties and fibre orientation in cross-laid needle-punched nonwoven fabrics

An attempt has been made to study the fibre cross laying as well as fibre orientation angle in cross-laid needle-punched nonwoven fabric and its relationship with tensile properties of fabric. Nine fabric samples have been produced by using three types of fibres, namely 100 % polyester, 100 % jute and 50:50 jute-polyester blend with three different numbers of layers (6, 12 and 18). The tensile properties of different cross-laid structures have been measured not only in machine direction (MD) and cross direction (CD) but also at different angles including the angle of laying with respect to the width of the fabric followed by ANOVA analysis in order to assess the nature of anisotropy in terms of tensile properties. It is observed that the number of layers in the web influences the cross laying angle (LA) as well as tensile properties of the fabric. The maximum tenacity is obtained in case of CD and then the tenacity gradually reduces towards the MD. The ANOVA analysis of the data reveals that the cross-laid needle-punched nonwoven fabric possesses reasonable isotropy in respect of both fibre orientation and tenacity in all the fabrics.