Multifunctional Antibacterial and Hydrophobic Cotton Fabrics Treated with Cyclic Polysiloxane Quaternary Ammonium Salt

A novel polysiloxane quaternary ammonium salt (NCTSi) was synthesized and used as antibacterial and hydrophobic agent for cotton fabric. The chemical structures were characterized by FT-IR. The surface morphology of treated cotton fabrics was characterized by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). The cotton fabrics treated with NCTSi showed excellent antibacterial properties against Gram-positive bacteria S. aureus and Gram-negative bacteria E. coli. The E. coli antibacterial rate was about 99.52 % and the S. aureus antibacterial rate was about 98.33 %, with only a slight decrease after 20 cycles of standard washing, to 91.43 % and 93.33 %, respectively. The inhibition zone was 2 mm and 2.5 mm against E. coli and S. aureus when NCTSi concentration was 4 %. The treated cotton fabrics provided excellent hydrophobic properties, and the water contact angle (WCA) reached 124.14 degrees compared to pure cotton fabrics. The mechanical properties and whiteness were also investigated. As a result of the performed modifications, multifunctional fabrics with a considerably increased hydrophobicity and high antibacterial property were obtained.