Preparation And Properties Of Antibacterial/Flame-retardant Cotton Fabric With S-triazine-based N-halamine

Textiles,as one of the personal protective equipments against environmental hazards,are irreplaceable in providing security and protection for the individuals.In recent years,textiles with single function have less to offer than people wish to have due to the increasing complexity of environmental threats,and the development of multifunctional textiles has attracted much attention.Cotton fabrics,as a kind of textile widely used and in close contact with human body,has outstanding comfortability,wearability,air permeability,biodegradability,warmth preservation and handle.However,the disadvantages of easy to breeding bacteria and flammability easily cause proliferation of diseased microorganisms and fire hazards,threatening folks'lives.Therefore,the preparation of antibacterial/flame-retardant multifunctional cotton fabric is of great significance to prevent harmful microorganisms spreading and fire,which is not only beneficial to protect people's life and property,but also to promote the development of functional textiles.Cyanuric chloride,as a common chemical intermediate,has high reactivity and thermostability.Its three chlorine can react with different compounds by controlling the temperature,which has been extensively used in the preparation of reactive dyes and functional finishing agents.Therefore,the preparation of reactive multifunctional finishing agent using the unique reactivity of cyanuric chloride to combine the antibacterial and flame retardant groups is an effective way to realize the preparation of antibacterial/flame-retardant multifunctional cotton fabric.In this paper,polycarboxylic and phosphate-containing N-halamine precursors based on s-triazine were prepared and the chemical structure was confirmed by FT-IR and NMR.The cotton fabric was modified by pad-dry-cure technique and the optimum finishing condition was explored.The antibacterial property,cytotoxicity,flame retardancy,thermal stability,combustion behavior,durability,physical and mechanical properties of the coated cotton fabric were studied.Firstly,a monochloro-s-triazine-based polycarboxylic N-halamine precursor(TIAPC)was prepared by introducing iminodiacetic acid and4-amion-2,2,6,6-tetramentylniperidine into the cyanuric chloride structure,and the effects of different metal ions(Cu²⁺?Ca²⁺?A1³⁺?Zn²⁺?Mg²⁺?Fe³⁺)on the flame retardancy of TIAPC-coated cotton fabrics were investigated.Compared with other metal ions,A1³⁺has a good catalytic char-forming ability,which can improve the char-forming capability of cotton fabric at high temperature,and has little effect on strength,air permeability and whiteness of cotton fabrics.However,the flame retardancy of TIAPC-coated cotton fabric is poor,which failed to pass the vertical combustion test,and the limiting oxygen index had little increase.On this basis,TIAPC-coated cotton fabric with excellent antibacterial property was obtained after chlorination by sodium hypochlorite.TIAPC-coated cotton fabric can kill about 10⁷CFU/m L of E.coli and S.aureus in 1 min of contact time,and has obvious inhibition zone,which has contact and release killing mechanism.Besides,TIAPC-coated cotton has good washing stability,storage stability and cytotoxicity.To solve the problem of poor flame retardancy of metal ion chelating TIAPC-coated cotton fabric,a phosphate-containing N-halamine precursor(TDAD)was designed and synthesized.TDAD not only constructed a P-N synergism flame-retardant system,but also improved its load on the surface of cotton fabric using high reactivity of dichloro-s-triazine structure.The introduction of phosphate group can effectively improve the flame retardancy of cotton fabric.TDAD-coated cotton fabrics can pass the vertical burning test with no afterflame/afterglow and 14.7cm of damage char length.The limiting oxygen index increased to 27.5%,and HRR and THR are significantly reduced during the combustion.The results show that the introduction of TDAD can significantly improve the char-forming capacity and reduce the release amount of flammable gaseous products during the process of thermal degradation and combustion of cotton fabric,which meant that TDAD possessed both gas and condensed phase flame-retardant mechanism.Meanwhile,TDAD-coated cotton fabric can kill E.coli and S.aureus within a short of contact time,which has contact and release killing mechanism.Besides,TDAD-coated cotton fabric has also good cytotoxicity,washing stability,storage stability,tensile strength and whiteness.In a word,the multifunctional cotton fabric with excellent antibacterial and flame-retardant performance was successfully prepared without affecting the comprehensive properties of cotton fabric,which laid a theoretical and scientific foundation for the design and preparation of multifunctional textiles,and provided ideas for the development of other multifunctional materials.