Study On The Manufacturing Processes Of Banana Stem Fibers

Recently,with the shortage of petroleum,coal and natural gas,the price of manufactured fiber raw material is rising.It is urgent to develop some new renewable natural resources.People have already payed great attention to the banana stem fiber as a nature ecology-friendly fiber.China is one of the major banana planting countries in the world.Every year,the output of banana in china is about five to six thousand tons.At the same time,almost the same amount of byproducts are produced,such as banana stem,banana leaf and so on. Most of these byproducts are discarded as garbage,they have not been developed and applicated well,and the farmland is polluted again.In this paper,we mainly studied on chemical degumming of banana stem fiber.First, we tested the chemical component of banana stem and the banana stem fiber which had been pretreated,this was used as reference to the next work.and by referring to other bast fibers degumming process,we studied the chemical degumming process to banana stem fibers by boiling one time,the pretreatment,boiling two times and so on.Several boil-off assistants were added to find the effect.At last,we choose this chemical degumming process:pickling→alkali- boiling→alkali-H₂O₂ boiling.The basic physical properties and the structure of banana stem fiber are also studied.The conclusions are respectively as follows:(l)The chemical component's character of banana stem fiber:the banana stem fiber which located different part of the banana trunk has different chemical component content; both the percentage of hemi-cellulose and lignin in banana stem fiber are high,which get to 25.25%and 15.87%respectively.So it brings difficulties to degumming.(2)The pickling,immerse and pretreatment of H₂O₂ were studied in this paper.The pretreatment of H₂O₂ has a good effect to remove lignin.The parameter of the pretreatment of H₂O₂ is:concentration of H₂O₂ 6g/L,pH 11,time 1.5h,heat-up time 35⁴0 min, normal pressure.(3)The primary chemical degumming process of banana stem fiber was taken as the follow route:Sample preparation→pickling→washing→boiling→washing→boiling(add H₂O₂)→acid washing→washing→dehydration→boiling→loosing→drying→banana stem fiber.The parameters of each process are:Pickling:concentration of H₂SO₄ 2g/L,temperature 55°C,time2h,normal pressure, bath ratio 1:20;Alkali boiling:boiling the first time:concentration of NaOH 6g/L,time 2h;boiling the second time:concentration of NaOH 8g/L,concentration of H₂O₂ 3g/L,time 2.5h,heat-up time 35⁴0 min,normal pressure,bath ratio 1:20;Souring:concentration of H₂SO₄ lg/L,time2³min,normal tempreture and pressure, bath ratio 1:20;Oil finish:BSK1.5%,10min,normal tempreture;According to parameter of chemical degumming,the banana stem fiber's residual gum content and residual lignin content are 10.25%and 3.29%respectively,fineness is 3.01tex,strength is 65.23cN,and extension is 2.86%.It has a primary ability in spinning.(4)Based on the test of banana stem fiber's shape structure,the longitudinal surface of banana stem fiber has crossing marking,and transect has hollow structure.It shows that the banana fiber has the shape characteristic of other bast fibers.(5)Based on the test of X-ray diffraction,the banana stem fiber's crystallization degree and degree of orientation are 69.66%and 0.8203.