Effects Of Acid And Alkali Treatment On The Structure And Tensile Properties Of Cashmere And Wool

Cashmere and wool are natural protein fibers,their chemical structure is very similar,they have commons in moisture,gloose,warmth and other aspects,are favored by people in the textile.But in the production the structure and performance of cashmere and wool fiber are easily vulnerable to acid and alkali damage,such as washing,bleaching,printing and dyeing process,which has been paid great attention.Fiber structure and performance damage will lead decline in quality of textile,and to bring great economic losses and distress to enterprises and consumers.Therefore,it is very important to improve the quality of cashmere and wool products by treating the cashmere and wool with hydrochloric acid and sodium hypochlorite to study the structure and tensile properties of the fibers and to find the factors that reduce the tensile properties of the fibers caused by the processing technology.In this paper,the structure and tensile properties of cashmere and wool fiber are studied as follows:1.The results showed that the concentration of acid and alkali solution,the treatment temperature and the treatment time were the main factors affecting the tensile properties.Three basic three-level design orthogonal test was used to test some basic indexes(broken strength,fracture time,fracture Elongation,etc.).The results showed that the treatment of cashmere and wool fibers with hydrochloric acid had a significant effect on the tensile properties of the bundles.The treatment of cashmere and wool fibers with sodium hypochlorite and the concentration of sodium hypochlorite The tensile properties have a very significant impact.2.The cashmere and wool fibers were observed by scanning electron microscopy.It was found that the low concentration of hydrochloric acid solution had less effect on the surface morphology of cashmere and wool fiber,but with the increase of the concentration,The destruction become more obvious,the scales began to tilt,a small part of the scales began to peel;while low concentrations of sodium hypochlorite solution on the cashmere and wool fiber damage has already begun,with the concentration increases,the damage will become more obvious,fiber Of the scaly layer is basically oxidized,the cortical layer begins to be damaged,the hair becomes rough,the concentration increases again,and even the cortical layer of the fiber is substantially destroyed,the hair part is oxidized and the whole fiber becomes unusually rough.3.Used separately X-ray energy spectrum(EDS)and X-ray diffraction(XRD).The results showed that the contents of C,N,O and S in the surface of cashmere and wool fiber treated with hydrochloric acid were not obvious,and the relative decrease of the crystallinity index was observed.The C element on the surface of the cashmere fiber treated with sodium hypochlorite The content of N,O and S decreased,and the content of N,O and S decreased,and the content of N,O and S decreased,and the relative crystallinity decreased.