Research On Chemical Composition And The Degumming Technology Of French Flax Fiber

Flax textiles plain natural,soft luster,because of its unique cool comfort and the characteristics of green health care,loved by the masses.Degumming process of flax fiber production still needs improvement.Flax degumming technology at home and abroad generally adopts chemical degumming method.Chemical degumming,mainly alkali scouring in scouring take a sodium hypochlorite and sodium chlorite to improve the efficiency of degumming.Chemical degumming process not only the damage of the fiber is large,the production equipment demand is higher,and degumming effect in general.At the same time,its production process will produce larger environmental pollution,harmful to human body health.In this paper,the problems of high energy consumption and pollution were discussed.Through continuous quantitative test the chemical composition of the French flax,and compared with domestic flax fiber content;By X-ray diffraction(XRD)analysis methods,the supramolecular structure form of the French flax fiber was determined;The pretreatment technology of French flax fiber was studied,and three different degumming schemes were worked out.Solution one: ultrasonic degumming;Solution two: adding ultrasonic assisted degumming in alkali oxygen bath;Solution three: the first step is to use pectinase pretreatment and then add the ultrasonic assisted degumming treatment in alkali oxygen bath.The conclusions are as follows:(1)The content of the French flax respectively: lipid-wax 1.06%,water soluble substance 2.96%,pectin 3.45%,hemicellulose 19%,cellulose 66.6%,lignin 4.22%,ash 0.68%;compared with pectin,hemicellulose and cellulose content of France flax fiber are higher than domestic flax fiber content;lipid-wax,water soluble substance and lignin contained are lower than domestic flax fiber content;ash content are similar.The internal molecular structure of the France flax fiber is very close,the fiber macromolecules in the crystalline region arrangement is neat,its original molecular orientation and crystallinity was a little higher than domestic flax fiber.The traditional degumming process will result in higher energy consumption and greaterpollution.In this paper,three kinds of energy saving and environmental friendly degumming processes were discussed according to the composition and structure characteristics of flax fiber.(2)The degumming effect of the three kinds of degumming process in order:Pectinase ultrasonic assisted chemical combined degumming>Ultrasonic assisted chemical degumming>Ultrasonic degumming.(3)On the basis of single factor experiment,the orthogonal experiment was used to study the degumming effect of different technological conditions,The results showed the optimum degumming process of pectinase ultrasonic assisted chemical combined degumming is that the pretreatment with pectinase concentration 2g/L;in the degumming process: degumming temperature 60?,H2O2 concentration 8%,NaOH concentration 6%,degumming time 80 minutes and ultrasonic frequency28 KHz.Comparing several degumming effect and the results of SEM scanning of flax fiber longitudinal structure: the degumming time of the pectinase ultrasonic assisted chemical combined degumming process is short and the degumming temperature is low,so the flax fiber cellulose hydrolysis is low.Single fiber strength is superior to the traditional chemical degumming of flax fiber,fiber damage is less,it can improve the process after the spinning performance.The degumming process not only ensures the degumming effect but also the environmental protection and energy saving at the same time.