Enhancing the mechanical properties of virgin and damaged jute/polypropylene hybrid nonwoven geotextiles via mild alkali treatment of jute fibers

Abstract

Nonwoven geotextiles made from hybridization of natural and synthetic fibers can potentially offer distinct advantages in terms of uniformity and improved mechanical properties. To further enhance the mechanical properties of hybrid nonwoven geotextiles, natural fibers such as jute must be treated with a minimal amount of alkali, such that the treatment process becomes scalable, cost-effective and environmentally friendly. Herein, we report a comparative analysis of physical and mechanical properties between the corresponding samples of untreated (UT) jute/polypropylene (PP) and mild alkali-treated (MAT) jute/PP nonwoven geotextiles in both virgin and damaged conditions. The constituent jute fibers were treated with 0.5 wt.% of sodium hydroxide solution under ambient temperature conditions for 24 h duration. Such mild treatment of jute fibers with alkali solution resulted in considerable improvement in the mechanical properties of MAT jute/PP nonwoven geotextiles corresponding to the sets of UT jute/PP nonwoven geotextiles. Various types of damage, including circular holes, horizontal cuts, vertical cuts and inclined cuts at an angle of 45°, were artificially induced in hybrid nonwoven geotextiles to investigate the reduction in tensile properties. Further, the Poisson's ratio in virgin and damaged states was determined to make a comparison between the UT and MAT jute/PP nonwoven geotextiles. In general, lower Poisson's ratio values were observed for mechanically damaged MAT jute/PP nonwoven geotextiles corresponding to the samples of UT jute/PP nonwoven geotextiles. Surprisingly, the vertical cuts induced in MAT jute/PP nonwoven geotextiles yielded tensile strength comparable to that of virgin samples.