Design And Synthesis Of Novel Antibacterial Agent And Its Application In Cotton Textiles Finishing

Textile has become a good medium of microbial attachment, reproduction and dissemination due to human skin secretion of sweat, sebum during use. Microbial contamination can damage the performance of textile itself, and some pathogenic bacteria may cause a cold, hand, foot, moss and other diseases, which will endanger the health of human beings. So, the antibacterial finishing technology emerged. With the improvement of living standard, antimicrobial textiles can not only satisfy the people's demand, but also played an important role in improving the level of health care and reducing the cross-infection of public environment and with vast market.In this paper, two novel reactive antibacterial agent have been synthesized, and finished to the cotton textile to give its efficiently antibacterial performance.(1) Reaction active groups-isocyanate was introduced through the reaction of isophorone isophorone diisocyanate(IPDI) and N, N-dimethyl ethanolamine, and terminal isocyanate sulfobetaine(ISB) was obtained by adding 1,3-PS.(2) long chain quaternary ammonium salt containing active groups- isocyanate(IQAS) was synthesized using N,N-dimethyl Octodecyl amine,3-bromo-1-propanol and isophorone diisocyanate(IPDI) as material. Then the structure was characterized by infrared spectroscopy(FTIR), nuclear magnetic resonance(NMR) and X-ray photoelectron spectroscopy(XPS).The cotton textiles were respectively treated with ISB, IQAS, and mixtures(1:1)by ionic interaction of finishing agent's isocyanate and hydroxyl group on the cotton fiber surface. The structure of cotton surface before and after finishing was characterized by FTIR and XPS, the surface topography was observed by SEM, which proved finishing agent was successfully grafted onto the surface of cotton textiles. In addition, this experiment also respectively finished the cotton textile with commercial antibacterial finishing agent AEM5700, SCJ-877, SCJ-2000 and made a comprehensive comparison with IQAS. Shaking method, plate count method and inhibition zone method were used to evaluate theantibacterial activity of antibacterial agent and treated cotton. Other properties(mechanical properties, permeability, hydrophilicity, thermal performance) have been tested. The animal test was used to evaluate toxicity of ISB and IQAS.The results showed that the minimum inhibitory concentration(MIC) of ISB for E.coli and S.aureus was 80 ?mol/mL, and MIC of IQAS for E.coli and S.aureus was 250 ?g/mL, 45?g/mL.The antibacterial rates for E.coli and S.aureus of cotton fabrics treated with ISB respectively were more than 99.5% and 99.9%, and treated cotton with good washability to reach AAA level, belongs to non-leaching antimicrobial fabric. Cotton fabric possessed good antibacterial adhension property after finishing with ISB, which can prevent the textile yellowing, smelliness. The mechanical properties(except breaking strength), hydrophilicity and moisture permeability of ISB finished cotton were improved. The animal experimental was used to evaluate safety of ISB. Lethality, changes in body weight, serum index, kidney and liver pathology proved that ISB is a safe and effective antibacterial material.This paper made comprehensive comparison of four cotton fabric finished with IQAS,AEM5700, SCJ-877, SCJ-2000 in antibacterial properties and another properties. The results showed that the antibacterial rate on E.coli and S.aureus of finishing cotton were more than99.99%. Moreover, the cotton textile treated with IQAS possessed high antibacterial efficiency, and could kill all bacteria in 3h. Treated cotton textiles are of good washability, the antibacterial effect can reach AAA level after 50 washing times, so they belong to non-dissoluble fabrics. In addition, IQAS improved the hydrophilicity of cotton, but the permeability decreased slightly. IQAS finished cotton textile improved the breaking strength,breaking elongation and bursting strength, and slightly reduced tearing strength. But the mechanical properties of IQAS treated cotton were comparable to the commercial products AEM5700, SCJ-877, SCJ-2000. The animal test results showed the mouse half lethal dose(LD50) of IQAS is 4088.83mg/kg, which proved IQAS belongs to the low toxic material.In order to give cotton fabric antibacterial and antibacterial adhesion properties at the same time, the mixture of ISB and IQAS(1:1) doubly finished cotton fabrics. The test results showed that the double treated cotton possessed efficient bactericidal effect on for E.coli and S.aureus, with high antibacterial rate(>99.99%). And it is good resistant to washing, andantibacterial effect to AAA level, belongs to non-dissolution of fabric. In addition, double finished cotton fabrics have good antibacterial adhesion performance. Double treated cotton improved the hydrophilicity, moisture permeability is slightly decreased. Mechanical properties before and after finishing differs little.