Synthetic fiber made of polyacrylonitrile or acrylonitrile copolymer containing more than 85% (mass percentage) of acrylonitrile. The common second monomer is non-ionic monomer, such as methyl acrylate and methyl methacrylate, and the third monomer is ionic monomer, such as sodium allylsulfonate.

Acrylic fiber is called artificial wool. It has the advantages of softness, bulkiness, easy dyeing, bright color, light resistance, anti-bacterial, and worm resistance. It can be pure spun or blended with natural fibers according to the requirements of different uses. Its textiles are widely used in clothing, decoration, industry and other fields.