Preparation Of N-Halamine Modified Microcrystalline Cellulose And Application In Antibacterial Materials

Microcrystalline cellulose,a kind of abundant green resource,was selectively oxidized to obtain oxidized microcrystalline in this research,which was further reacted with N-halamine compound to prepare antibacterial N-halamine modified oxidized microcrystalline cellulose.The N-halamine reacted with lysine and fixed onto the oxidized microcrystalline cellulose,and further adsorbed copper ions to prepare organic-inorganic composite antibacterial materials,which were blended with poly?vinyl alcohol?to prepare antibacterial films.Finally,the antibacterial cotton fabric was obtained by coating organic-inorganic composite antibacterial materials.First,we synthesized 3-?2-aminoethyl?-5,5-dimethylhydantoin?ADMH?and immobilized onto the oxidized microcrystalline cellulose to obtain N-halamine modified oxidized microcrystalline cellulose?OC?precursor OCADMH.The structure of N-halamine precursor was characterized by FTIR,¹³C NMR and element analysis?EA?.The storage stability of the chlorinated OCADMH-Cl was tested.The morphology and crystallinity of the oxidized microcrystalline cellulose were characterized by SEM and XRD.Finally,the antibacterial films?PVA/OCADMH-Cl?were obtained by mixing OCADMH-Cl with PVA.The surface morphology and chemical structure of the films were characterized by SEM,FTIR and XRD.The thermal stability and antibacterial properties of the films were also tested.S.aureus with a concentration of 1.31x10⁶ was completely killed within 60 min,while E.coli O157:H7 with a concentration of 2.67x10⁶ was killed within 30 min by contacting with the antibacterial films.The thermal stability of the composite membrane was decreased in some degree.Second,the intermediate product Ly-ADMH was obtained by fixing lysine onto 3-?2-aminoethyl?-5,5-dimethylhydantoin.And Ly-ADMH was immobilized onto oxidized microcrystalline cellulose to obtain N-halamine precursor OC-Ly-ADMH.Then,copper ions were adsorbed to prepare OC-Ly-ADMH/Cu²⁺.After chlorination,OC-Ly-ADMH-Cl/Cu²⁺was blended with PVA to obtain antibacterial film(PVA/OC-Ly-ADMH-Cl/Cu²⁺).The structures of Ly-ADMH,OC-Ly-ADMH-Cl/Cu²⁺and PVA/OC-Ly-ADMH-Cl/Cu²⁺were characterized by FTIR,¹H NMR,EA and XRD,and the thermal stability and antibacterial properties of the antimicrobial membranes were also tested.The prepared antibacterial composite membranes could inactivate S.aureus with a concentration of 2.33x10⁶ within 10min and E.coli O157:H7 with a concentration of 3.90x10⁶ within 5 min.The thermal stability of composite membrane has been improved.Third,the N-halamine precursor OC-Ly-ADMH/Cu²⁺was coated on cotton fabrics after optimizing the process condition.It was characterized by FTIR.The washing stability,breaking strength and antibacterial properties before and after chlorination were tested.The results showed that the washing stability and breaking strength of the cotton fabric were improved.The antibacterial coated cotton fabric could kill S.aureus with a concentration of8.33x10⁵ within 10 min,and kill E.coli O157:H7 with a concentration of 1.03x10⁶ within 60min.