1. Form The longitudinal surface of polypropylene is straight and smooth, and the cross section is round. 2. Density The biggest advantage of polypropylene fiber is its light texture. Its density is only 0.91g/cm3, which is the lightest variety among common chemical fibers. Therefore, polypropylene fiber of the same weight can obtain a higher coverage area than other fibers. 3. Strength and elongation Polypropylene has high strength, large elongation, high initial modulus and excellent elasticity. Therefore, polypropylene fiber has good abrasion resistance. In addition, the wet strength of polypropylene is basically equal to the dry strength, so it is an ideal material for making fishing nets and cables. 4. Hygroscopicity and dyeability Polypropylene has very little hygroscopicity, almost no moisture absorption, and the moisture regain under general atmospheric conditions is close to zero. But it has a wicking effect and can transmit water vapor through the capillary in the fabric, but it does not have any absorption effect. Polypropylene fiber has poor dyeability and incomplete chromatogram, but the coloring of the original solution can be used to make up for the deficiency.