1. PP yarn shape: The longitudinal surface of polypropylene is straight and smooth, and the cross section is round.

2. PP yarn density: The advantage of polypropylene fiber is that it is light in texture, and its density is only 0.91g/cm3, which is the lighter density variety among common chemical fibers.

3. PP yarn tensile strength: polypropylene yarn 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 yarn is basically equal to the dry strength.

4. PP yarn hygroscopicity and dyeability: polypropylene has very little hygroscopicity, almost no moisture absorption, and the moisture regain rate under ordinary atmospheric conditions is close to zero. But it has a wicking effect and can transmit water vapor through the capillary in the fabric, without any absorption effect by itself.

5. PP yarn is acid and alkali resistant: Polypropylene fiber has good chemical resistance. In addition to concentrated nitric acid and concentrated caustic soda, polypropylene fiber has good resistance to acids and alkalis.

6. PP yarn light resistance: Polypropylene fiber has poor light resistance, poor thermal stability, easy aging, and is not resistant to ironing. But it can improve its anti-aging performance by adding anti-aging agent during spinning. In addition, polypropylene fiber has good electrical insulation, but it is easy to generate static electricity during processing.