Study On Ultrastructure Of Ramie Fiber By Enzymatic Method And Study On Its Fabric Modification

As a kind of natural high quality ramie fiber,its single fiber has long bast fiber length,moisture absorption,moisture excellent characteristics of fast speed,but due to its high strength,high young’s modulus,as well as single cell has led to its tip on taking has been curbed,thus to explore the internal structure of the fiber is imminent.The traditional method of skinning ramie fiber by chemical method was used to study its structure.Therefore,the use of biotechnology and enzymology for research meets the needs of development,and the mild treatment conditions reduce the cost and meet the purpose of clean production.In this study,xylanase and laccase were used to analyze ramie fiber structure by exfoliating ramie fiber layer by layer.In order to prove the specificity of the enzyme to remove the corresponding substrate and then remove it,the enzyme activity analysis and substrate specificity detection of the commercial enzyme used were made.In the enzymatic peeling reaction,a single enzyme and a complex enzyme were combined to peel the bast fiber layer by layer to explore its cross-sectional structure and longitudinal structure.With the help of ramie fiber fabric--grass cloth provided by jiangxi wanzai grass cloth factory,the modified graft silk protein was studied.(1)Pectinase,xylanase and laccase were found to be able to degrade their traditional substrates by specific substrate detection.The results showed that pectinase could not degrade xylan and cellulose.However,both xylanase and laccase can degrade cellulose slightly.Xylanase also slightly degrades pectin.(2)In the process of peeling the bast fibers with enzymes,it was found that the bast fibers had three-layer structure,including L1 layer,L2 layer and L3 layer from outside to inside,among which L1 was rich in xylan.Stripping off the L1 layer,the fibers become twisted and broken longitudinally,revealing the fibrillar structure and kink deformation.Laccase treatment can expose the holes in the secondary wall.The holes in the main wall are like grain holes and the holes in the dislocation area are irregular.L2 is the thickest layer and has different chemical compositions from L1 and L3.The shape of L3 layer is closed tubular,the top is round and blunt,and the inner wall is honeycomb,showing blue fluorescence.(3)The holes in the secondary wall of ramie fibers and the honeycomb hydrogel structure in the inner layer of ramie fibers will be the physical basis for ramie’s rapid desiccation,wrinkling and itching.(4)Ramie fiber was grafted and modified by 10 g/L sodium periodate oxidized at 40℃ for 35 minutes,and then grafted into 10 g/L and 55℃ silk protein,so that the fabric had strong skin-feeling and improved softness under the condition of strong availability.Through this technology,it is expected to provide powerful help for the application of ramie fiber.