4. Polypropylene Fiber: Rich source of raw materials, low price, simple production process, rapid development. The biggest characteristic of polypropylene fiber is its small proportion, lighter than water (3/5 of cotton fiber), and lightest of all fibers. Products have medium elasticity and resilience, not easy to wrinkle, no ball. Polypropylene fibers are difficult to dye, usually in the original solution. The hygroscopicity of polypropylene fibers is very poor, but polypropylene fibers have a strong wicking effect. Water vapor can be eliminated by capillaries in the fibers. After clothing is made, its comfort is better. Especially the superfine polypropylene fibers, because of the increase of surface area, can transfer sweat more quickly and keep the skin comfortable. Polypropylene fibers have poor light and sunshine resistance, easy aging and poor heat resistance, and begin to shrink above 100 ℃.
