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Differentiated polypropylene fiber is a term used in the chemical fiber industry. It refers to a chemical fiber that is different from the conventional one. It is usually used to describe the technological transformation of a conventional chemical fiber type to create a chemical fiber with a certain characteristic.

Differentiated polypropylene fibers, conceptually speaking, have some differences with functional fibers. The former mainly improves the performance of taking, while the latter highlights special properties such as high temperature resistance, corrosion resistance, high strength and high modulus. However, the difference between the two is gradually blurred and inseparable, and functional fibers are also considered as differential fibers.

There are many varieties of differentiated polypropylene fibers, which are currently susceptible to dyeing, coloring, high moisture absorption, water resistance, high shrinkage, antistatic, antipilling, antibacterial, flame retardant, far infrared, anti-ultraviolet, luminescent, irregular, fine denier, super Fine denier, compound and other varieties.

Differentiated polypropylene fibers can be obtained by chemical modification and physical modification. The main points are as follows.

The main method in the chemical modification method is the copolymerization method, that is, the introduction of certain special genes in the basic structure of macromolecules and their copolymerization, such as in the production of polyesters from terephthalic acid (PTA) and ethylene glycol (EG). A small amount of cationic dyeable polyester can be obtained by introducing a small amount of sodium dimethyl isophthalate (SIPM).

In the physical modification method, there is a blending method, that is, a specific modifier (or additive) is mixed into the polymer melt or solution before spinning, and then the spinning is performed, so that the modifier can be Evenly mixed in the fiber. Antibacterial fibers, for example, are added to the polyester melt and then spun. In addition, changing the macroscopic structure of the fiber is also an important method of physical modification. For example, two different polymer melts or their solutions are passed through a special dispensing device so that each fiber spun from the fiber contains these two components. That is, the composite fiber; the fiber can also be microporous, cross-section profile, surface roughening and so on.