Preparation And Structure And Properties Of Cellulose Fiber From

The attention and researche on Biomass materials have received more and more extensivein various industriesbecause of its green, renewable and bio-degradation, etc. As a biomass raw material,if saballeaf cellulosecanuse effective processing method combined with the fiber material, not only it can produce certain economic benefits, also reduce the the crisis brought about bynon-renewable resource consumption. In this topic, the dissolved performance of sabal leaf cellulosewas studiedin a solvent system of lithium chloride / dimethylacetamide, and the wet spinning process of resulting solutionwas explores.The spun fibers were crosslinked modification, and the structure and properties of the fiber before and after crosslinking were studied.Firstly, the dissolved performance of sabal leaf cellulosewas studied in a solvent system of lithium chloride/dimethylacetamide. By the comparative study of degree of polymerization of the cellulose, crystalline structure, FT-IR and dissolution rate before and after activation, solution viscosity of sabal leaf cellulose from different activation methods(replacement of water and other solvents, ultrasonic, thermal dimethylacetamide, thermal dimethylacetamide and KMnO4 method). Thermal dimethylacetamide and KMnO4 activation method was used to activat cellulose before dissolvingcellulose. The effect of concentrationof lithium chloride, cellulose content, dissolution temperature, dissolution time on cellulose dissolution rate and solution viscosityin the dissolutionprocess were discussed by single factor and orthogonal experiments. The results showed that the preferred dissolution conditions of activatedsabal leaf cellulose in lithium chloride/dimethylacetamide dissolution system is that lithium chloride concentrationof 80 g/L, heating time 2.5 h, heating temperature 120 ℃.Secondly, this topic mainly discusses the impact of wet spinning process conditions on the mechanical property of sabal leaf cellulose fibre.Through test and analysis found that the optimum wet spinning processwere that spinning nozzle aperture 0.08 mm, the spinning temperature 45 ℃, coagulation temperature30 ℃, coagulation bath of an aqueous solution containing 2.5% dimethylacetamide, stretching bath temperature 40 ℃, draw ratio 1.5, then the resultant fibers had a linear density of 7.52 dtex, a breaking strength of 1.724 cN / dtex.In addition, the spun fibers were modified by glutaraldehydecrosslinking, studied the influence of glutaraldehyde concentration, crosslinking time, crosslinking temperature on the mechanical properties of the fibers. And the structure and properties of the fibers were tested before and after crosslinking. The results showed whenthe crosslinking condition wasglutaraldehyde concentration of 5%, crosslinking time 60 min, crosslinking temperature 50 ℃, the performance of the resulting fibers were better, linear density of 9.57 dtex, a breaking strength of 2.23 cN / dtex. After crosslinking, fibers moisture regainof absorption and desorption(absorption: 14.57%, desorption: 13.62) were less than before crosslinking(absorption: 15.44%, desorption: 14.84); The results of X-ray diffraction analysis showed that crystal formof fiberswere unchanged after crosslinking, the degree of crystallinity increases from 48.69% before crosslinking to 57.18%; Infrared spectrum analysis showed that the acting forceof molecular hydrogen bonding between the fibers was weakenedafter crosslinking, also found an amidogne there. Scanning electron microscope showed the fiber surface becomes roughafter crosslinking, more fluff is produced, the grooves more obvious than the former; Thermogravimetric analysis results showed that the thermal decomposition temperature of the fiber is reduced after crosslinking, but the former is higher of the weight of the residues, for the protection of the structure and properties of the fibers, the fibers temperature should be controlled within 200 ℃.