The Separation Degree Of The Cotton-stalk Bast Fiber And Its Influence On Fiber Properties

Our country is a major cotton producing country in the world, so it has a very rich resources of cotton-stalk bast. Using agricultural waste resources, cotton stalk bast, to develop natural textile materials can ease the shortage of textile industrial raw materials and natural fiber resources in our country, but also consistent with goals of sustainable use of resources and environmental protection. However, the degummed cotton-stalk bast fiber is still not ideal, the residual gum and lignin content is relatively high, and generally coarse, difficult to apply directly to the spinning process.In this paper, we mainly researched the separation degree of cotton-stalk bast fiber,that is, under different conditions, sufficiently separating cotton-stalk bast fiber and exploring the degree and regularity of fiber separation and analyzing the influence of different degree separation on fiber properties and morphology. The greatest separation degree and its condition of cotton-stalk bast fiber are obtained by studying.Firstly, this experiment use penetrant and bulking agent to chemically pretreat the degummed cotton-stalk bast fibers, and release the dense structure of the processing fibers so that Na OH able to enter into a deeper place inside the fibers to remove partial glial to make the fibers become thinner while reducing the binding force between fibers,increasing the original defects and cracks of fiber surface. Next, put the ultrasonic wave in the fibers after chemical pretreatment, and make the fibers produce concentration of stress and strain at the original defects and cracks, part of the energy transmitted by ultrasonic waves will be converted to the energy required by cracks when they expand the new surface, to cause crack propagation, fiber separation. By single factor experiment,orthogonal experiment and visual analysis, in fineness indicators, the optimized process conditions of chemical pretreatment, ultrasonic vibration and combinations thereof three separate processes are studied, and by comparing properties and microstructure morphology of fibres which are from the optimum conditions, the optimization under the greatest separation degree is obtained.Through experiments, optimization of process parameters for the chemical pretreatment is: additives 120 g/L, Na OH 10g/L, time 90 min, temperature 50℃, liquor ratio 1:20, and the fineness of the fibers obtained these conditions is 3.54tex; optimization of process parameters for the ultrasonic vibration is: Na OH 12g/L, the power 160 W, time50 min, temperature 80℃, liquor ratio 1:20, and the fineness of the fibers obtained these conditions is 3.07tex; optimization of process parameters for the combinations process is:Na OH 20g/L, additives 140g/L, the power 160 W, temperature 70℃, time 90 min, liquor ratio 1:20, and the fineness of the fibers obtained these conditions is 4.18 tex.The fineness of degummed cotton-stalk bast fibers is 4.55 tex. The fineness of fibers from program one, that is chemical pretreatment and ultrasonic vibration is 3.07 tex. The fineness of fibers from program two, that is combinations process is 4.18 tex. Comparing these two programs, the separation degree of cotton-stalk bast fiber of program one is greater than program two.