The Modification Of Para-aramid Nanofibers By Using Ionic Liquid-transition Metal And The Application In Flame-retardant Cotton Fabric

Cotton fabric shows excellent moisture absorption,biocompatibility,and degradability,which has been widely used in vehicle decoration,clothing,furniture,and other industries.However,it is easy to breed bacteria and cause severe indoor fires.In this paper,a new type of flame-retardant,smoke suppression,toxicity reduction and the bacteriostatic cotton fabric was prepared by step-by-step dip-coating epichlorohydrin modified para-aramid nanofiber solution(AEP),ionic liquid(IL),Cu SO4·5H2O and phytic/chitosan solution(PA@CS)on the surface of cotton fabric.The main research contents and conclusions are as follows:(1)Cot/AEP/IL is prepared,where AEP is bonded to cotton fabric by hydrogen bonding,and IL is grafted to AEP by a ring-opening reaction.Cot/AEP/IL is selfextinguishing with a char length of 111 mm.The peak heat release rate(p HRR)and total heat release rate(THR)of Cot/AEP/IL are reduced by 42.5% and 58.8%,respectively,compared with untreated Cotton.The possible flame retardancy mechanism of AEP/IL was revealed by the analysis of condensed phase and gas phase products based on pyrolysis or combustion.The average tensile strength in the warp direction of Cot/AEP/IL is increased from 129 N to 167 N,and increased from 125 N to 155 N in the weft direction.The softness of the modified cotton fabric is well retained.In conclusion,Cot/AEP/IL has good fire safety and mechanical properties.(2)Cot/AEP/IL was soaked in Cu SO4 solution to get Cot/AEP/IL/Cu.The finishing of AEP/IL/Cu endows cotton fabric with flame retardancy,smoke suppression,toxicity reduction,and antibacterial properties.Compared with Cotton,The p HRR and THR of Cot/AEP/IL/Cu decreased by 43.7% and 41.7%,respectively.Compared with Cot/AEP/IL,the peak smoke production rate(p SPR)of Cot/AEP/IL/Cu decreased by77.0% and total CO production decreased by 40.5%.Cot/AEP/IL/Cu significantly inhibited the activity of Escherichia coli(E.coil)and Staphylococcus aureus(S.aureus).(3)Cot/AEP/IL/Cu is soaked in PA@CS solution to get Cot/AEP/IL/Cu/PA@CS.Cot/AEP/IL/Cu/PA@CS was self-extinguishing and with a char length of 59 mm.Compared with Cotton,the p HRR and total smoke production(TSP)are reduced by48.1% and 63.5%,respectively,showing the best comprehensive effect among all samples.Cot/AEP/IL/Cu/PA@CS has excellent antibacterial performance.In conclusion,Cot/AEP/IL/Cu/PA@CS shows good comprehensive properties in flame retardancy,smoke inhibition,toxicity reduction,and bacteriostasis.