PREDICTION OF POLYPROPYLENE YARN PROPERTIES

摘要

The models for prediction of polypropylene yarn packing density and strength are described. These models are based on the characteristics of fibers and yarns and also on the technological and material parameters of yarns. Groups of polypropylene yarns were spun in the pilot plant from the smallest to the greatest possible twist factor. Polypropylene fibers with different fineness, strength and deformation at break were used for yarn production. Radial and effective packing density were measured based on yarn cross-section analysis. For prediction of yarn packing density Neckar model was used. For prediction of yarn strength the fiber bundle strength, fiber elongation factor, yam packing density and fiber orientation factor can be used. While studying the effect of the twist coefficient on the strength of polypropylene yarn the mechanism different from cotton yarn strength was found. Influence of fiber fineness on yarn packing density and strength was illustrated, too.