Development And Research Of Chitin Antimicrobial Knitted Fabric Based On The Chemical Modification

Chitin fiber is a safe raw material which has good hygroscopicity,biocompatibility, biodegradability and bacterial inhibition. But researches show that ithas bacterial inhibition not bactericidal action. The purpose of this article is enhancingits micro-organism resistance after the chemical modification on the chitin fiber,based on the mechanical property is not significant lower. So we can consummate thespinning technology of chitin fiber, reduce the cost, and achieve the growing demandof health protection for people.On the basis of the test and analysis of chitin physical properties, we did someamine group modification on the surface of chitin fiber. First chitosan acted withsalicylaldehyde generating schiff base, then deacidizinged by sodium borohydride, atlast it reacted with iodomethane by the catalysis of sodium hydroxide and sodiumiodide, so we obtained quaternary ammonium chitin fiber.The chitin fibers were dealt with swelling first, because it is good for quaternaryammonium chemical modification. During the whole experiment process, weanalysed and optimized the process using single factor analysis and orthogonalexperimental method, finally we got the optimum chemical modification: Swelling:the reagent is60%ethyl alcohol,and reacted at60℃for2hours; Acetal: the dosage ofreactant is chitin fiber: salicylaldehyde=1:0.5, and reacted at70℃for2hours, at thesame time the PH value of reactant is kept at7; Reduction: the dosage of reactant ischitin fiber:sodium borohydride=1:1, and reacted for30min at30℃; Quaternaryammonium change: the dosage of reactant is chitin fiber: reaction assistant:iodomethane=1:0.5:0.5, and reacted for60min at60℃. The breaking tension ofquaternary ammonium chitin fiber is3.32cN, the breaking elongation rate is7.64%,and the degree of the quaternary ammonium is0.69%. The strength of the modifiedfiber is decrease, but it is acceptable.Through the antibacterial test for the chitin fiber and modified on Escherichiacoli and Staphylococcus aureus, we concluded that the bacteriostatic rate of chitin fiber and modified fiber to escherichia coli was58.7%,93.2%, and to staphylococcusarueus was62.5%,95.8%. Compared with no modification of chitin fiber, thebacteriostatic rate of quaternary ammonium chitin fiber increased signigicantly.Based on the understanding of physical performance of chitin blended yarn, wedeveloped some different antibacterial knitting fabrics by using the characteristics ofchitin fiber and the organizational structure. First we knitted a common organizationin STOLL CMS530HP computer flat knitting machine, then handing the fabric withmethod of chemical modification described above, and tested the basic performance,at the same time analyzed the wear ability by fuzzy-integrative evaluation method,and we found the fabric developed satisfied the antibacterial functional knitted fabricquality standards, so chitin yarn is more suitable to develop antibacterial knittedfabric.Through the antibacterial test for the chitin fabrics and modified fabrics onEscherichia coli and Staphylococcus aureus, we concluded that the bacteriostatic rateof chitin/cotton blended fabric and modified fabric to escherichia coli andstaphylococcus arueus was44.2%,35.7%,84.2%,83.7%, and chitin/tensile blendedfabric and modified fabric was46.4%,40.3%,85.4%,84.3%. Compared with nomodification of chitin fabric, the bacteriostatic rate of quaternary ammonium chitinfibric increased signigicantly, and achieved the national antibacterial standard.