Abstract:

A cationic surfactant, i.e., a quaternary ammonium salt namely C16-GPBCH, was synthesized through a one-step nucleophilic substitution reaction, with the yield of 89%. The molecular structure of the product was characterized by ¹H NMR and Fourier transform infrared spectroscopy, confirming its high purity and consistency with the expected structure. Then, C16-GPBCH was applied to the functional finishing of cotton knitted fabrics by impregnation method. The influences of those process parameters such as the mass concentration of the finishing solution, water bath temperature, and the pH upon the antistatic and antibacterial properties of fabrics were investigated. The results showed that, when the mass concentration of the finishing solution was 30 g/L, the water bath temperature was 70 ℃, and the pH was 8, the finished fabric exhibited the best comprehensive performance: The static half-life was significantly shortened to 12.8 s, and the peak voltage was reduced to 912 V. Compared with the untreated fabric, the half-life and peak voltage were decreased by 79.5% and 40.1%, respectively. In addition, the antibacterial rates against Escherichia coli （E. coli） and Staphylococcus aureus （S. aureus） reached 99.95% and 99.99%, respectively, indicative of obvious inhibition zones, which demonstrated excellent dual antibacterial mechanisms of contact killing and diffusion killing. This work might provide important experimental basis and theoretical support for constructing an efficient and multifunctional finishing process for cotton fabrics.

Key words: quaternary ammonium salt, surfactant, cotton knitted fabric, antibacterial, finishing performance