In this work, n-alkyl chitosan (N-CTS) was obtained by alkylation modification of chitosan with n-butylaldehyde using Schiff alkali method. The etherifying agent 3-chloro-2-hydroxypropyl triethylammonium chloride (CHPTAC-ethyl) was synthesized from triethylamine and epichlorohydrin. The N-CTS and CHPTAC-ethyl were etherized to finally synthesize n-alkyl quaternary ammonium chitosan (N-CCTS). Scanning electron microscope, X-ray diffractometer, Fourier transform infrared, X-ray photoelectron spectroscopy, and 13 CNMR were used to characterize the surface morphology and chemical structure. Viscosity method and spectrophotometry were used to determine its physical and chemical properties. The etherification reaction mechanism was studied systematically and the influence of reaction conditions on the degree of substitution and solubility of N-CCTS was investigated. The minimum inhibitory concentration (MIC) of N-CCTS against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was both 0.15 g/L, which was superior to the MIC value of natural chitosan. N-CCTS was used to finish rabbit hair fabric with citric acid as cross-linking agent and sodium hypophosphite as catalyst. The antibacterial and washing resistance of the product were investigated. After 25 times of washing, the antibacterial rate of N-CCTS against E. coli and S. aureus remained stable at about 90%, and the antibacterial rate was higher than that of N-CTS and natural chitosan, and it was a kind of natural polymer longacting antibacterial finishing agent for rabbit hair fabric.

Alkylated chitosan was obtained by alkylation of chitosan(CTS) with n-butyraldehyde, the product was then reacted with trichlorodihydroxypropyl triethyl ammonium chloride(CHPTAC-ethyl) to form n-alkylated quaternary ammonium chitosan. Its chemical structure was characterized by FTIR, and its physicochemical properties, such as viscosity-average molecular weight and solubility, were determined by viscosity and spectrophotometry. The antimicrobial activity of the modified chitosan was determined by the minimal antimicrobial method, and the minimum effective antimicrobial concentration (MIC) of the product against escherichia coli was 0.15g/L, which was better than the MIC value of the natural chitosan. Using citric acid as cross-linking agent and sodium hypophosphate as catalyst, the antibacterial finishing of rabbit hair fabric with modified chitosan showed that the antibacterial rate of n-alkylated quaternary ammonium chitosan to Escherichia coli was over 99.9%, and the antibacterial rate was better than that of natural chitosan, and it was a kind of good natural macromolecule antibacterial finishing agent for animal hair fabric.

N,N-dialkylchitosan (N,N-CTS) was modified by n-butyraldehyde using Schiff base method, it is then synthesized with N,N-CTS by etherification with 3-chloro-2-hydroxypropyltriethylammonium chloride (CHPTAC-ethyl). FTIR and spectrophotometry were used to characterize their chemical structure and physical and chemical properties. The minimum antibacterial activity of the modified chitosan was determined by the minimum bacteriostatic method, and the minimum effective bacteriostatic concentration (MIC) of Escherichia coli was 0.2 g/L, which was better than that of natural chitosan. The antibacterial effect and washing resistance of rabbit wool fabric were investigated by using modified chitosan. After washing for 10 times, the results showed that the inhibition rate of N,N-CCTS on escherichia coli was still more than 99.9%.