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Pectin and lignin are both very important noncellulosic substances occurring in hemp fibers. The main task in preparing hemp fibers for textile applications is to remove these noncellulosic substances without damage to the fiber cellulose. Pectin and lignin in hemp before and after chemical processing are characterized by infrared spectroscopy. The influence of chemical processes, fiber regions, and alkaline boiling parameters on lignin and pectin removal are investigated in this paper. The results indicate that the alkaline boiling process is effective for removing pectin and lignin. There is no residual pectin in the fibers after the alkaline treatment, but there is a residual level of lignin. The concentration levels of both sodium hydroxide and sodium sulphite have significant effects on lignin removal, and there are variations in lignin properties and accessibility from the lower to the upper regions of the hemp stem.

This is a review article of the various experimental approaches used for measuring fabric mechanical properties important in apparel handling, including the biaxial tension and in-plane shear parameters. First, the paper discusses the important issues encountered during such a fabric test. Then most existing biaxial tension and shear fabric testers are introduced and critically analyzed. Based on this information, a new tester concept is proposed in which tensile and shear forces can be applied simultaneously.

Although it is undeniable that the Poisson's effect on the behavior of a woven fabric is crucial, there have been relatively few papers devoted to this subject. In this study, a mechanical model for a woven fabric made of extensible yarns is developed to calculate the fabric Poisson's ratios.Theoretical results are compared with the available experimental data. A thorough examination on the influences of various mechanical properties of yarns and structural parameters of fabrics on the Poisson's ratios of a woven fabric is given. The prediction of Poisson's ratios in this paper will enable more rigorous studies on such important issues of fabric bending and draping behaviors.

In this replicated experiment, we investigated the impact of cashmere in blends with superfine wools on the mechanical properties of single jersey knitted fabrics. We also investigated the relative performance of soft, low crimp/low fiber curvature superfine wool when compared with cashmere and also when compared with traditional high crimp/high fiber curvature superfine wool in pure and blended knitted fabrics. The results indicate both the cashmere blend ratio and fiber curvature/crimp of wool affected fabric properties. Pure cashmere fabrics were softer than pure wool fabrics. Adding cashmere to wool increased knitted fabric softness, smoothness, flexibility, and suppleness. The physical properties of pure low crimp wool fabrics were closer to the properties of pure cashmere fabrics than were knitted fabrics made from pure standard wool.