Ｔｈｅ Ａｎｔｉｍｉｃｒｏｂｉａｌ Ａｃｔｉｖｉｔｙ ｏｆ Ｗｏｏｌ Ｆａｂｒｉｃｓ Ｔｒｅａｔｅｄ ｗｉｔｈ Ｃｒｏｓｓｌｉｎｋｉｎｇ Ａｇｅｎｔｓ ａｎｄ Ｐｏｌｙｈｅｘａｍｅｔｈｙｌｅｎｅ Ｂｉ

In this study， we used citric acid (CA) as a crosslinking agent， mixed with polyhexamethylene biguanide， to perform a pad-dry-cure treatment on wool fabrics to study its antimicrobial effects and physical properties. The surface characteristic and the structure of wool fabric were investigated by means of scanning electron microscopy (SEM）. Fourier transform infrared spectroscopy (FTIR) was employed to study the crosslinking mechanism of the treated fabric. The concentration of finishing agent polyhexamethylene biguanide in the presence of citric acid as well as the treatment conditions significantly affected the performance properties activity of treated wool fabrics. The treated wool fabrics showed good antimicrobial activity. From the experimental results， we learned that polyhexamethylene biguanide and CA did not crosslink with the wool fibers if the wool fabrics were not oxidized by hydrogen peroxide and that after oxidization， CA produced esterification with the -OH group of the wool and transamidation with the NH2 group of the polyhexamethylene biguanide to form a crosslink. The surface crosslink of the oxidized wool fibers were relatively coarse， which beneficial for the antimicrobial and antiseptic effects of the wool fabrics.