Study On The Microdissolution Process Of Hemp Fabric And Its Taking Performance

Hemp fiber is a kind of natural fibers with the advantages of moisture absorption,anti-bacterial and anti ultraviolet properties.So many scholars gradually get attention to hemp fibers these years.In the past,most papers were on fiber structures,properties,processing technology,yarns,and other areas of development.However,the researches of hemp fabrics were only a few.This study focused on the effects ofN-methylmorp ho line-N-oxide(NMMO)and lithium/N,N-Dimethylacetamide chloride(LiCl/DMAc)micro-dissolution process on hemp fabrics and their influences on the fabric properties,which had guided significance to the application of hemp fabrics in the textile field.Firstly,hemp fabrics were treated by NMMO solvent.In the experiment,NMMO concentration,temperature and time were been set up to measure the four typical properties for fabric stiffness,wrinkle recovery property,ability of water management and air permeability.Through the three factors and three levels orthogonal experiments,the optimal process of NMMO micro dissolution of hemp fabric was:NMMO concentration,processing time and processing temperature for 30%,45min and 64 ?;At the same time,fabics were treated by LiCI/DMAc micro dissolution solution.There were 3 kinds of pre-treatment methond for using distilled water,DMAc sodium and alkali?After that,fabris were dissolved in 10%LiCl/DMAc solution.By analysing the related performance results,the optimal treatment process for hemp fabrics was determind as follows:15%concentration of alkali pretreatment for 45min.10%LiCI/DMAc for 120min;The micostrusture of hemp fibers was analyzed by using scanning electron microscope,the microstructure of Fourier transform infrared spectrum and X-ray diffraction analysis.SEM results showed that hemp fibers were more smooth and cross section reduce fine lines after micro dissolution treatment;FTIR results showed hemp fibers absorption peak did not migrate but just the intensity change,lignin and pectin were partialy removed;XRD results showed that the change of hemp cellulose crystal after NMMO treatment,so the fiber strength was low,after the treated by LiCI/DMAc hemp was still observed type I of cellulose and cellulose crystallinity increased;Then,the wear behavior of hemp fabrics after NMMO and LiCl/DMAC treatment were studied,basic structural properties,appearance and comfortable capacity were included.Major conclusions were as follows:The thickness of the fabrics increasing,the warp and weft density become larger,and the square of meter weight decreased slightly;Breaking forces were reduced more or less after NMMO treatment,while elongation at break increased obviously,the tensile properties of LiCl/DMAc were better than that of NMMO.The properties of rigidness and softness,wrinkle recovery and drape performance were improved.The fabric improvement by using NMMO process was more obvious.The comfort performance of the fabric was generally improved,the air permeability of the fabric was decreased,the liquid water management ability was improved,and the core suction performace was improved;Finally,some conclusions about fabric style were acquired by KES-FB system.Elasticity and limpness of the fabrics improved,the fabrics became more plump and smooth.In a word,the wear behavior and febric style became better after micro dissolution treatment,which washelpful to the development of hemp fabric in the future.