Studies Of The Cellulose Fiber By The Method Of Cellulose Carbamate

Cellulose carbamate(CC) is an alkali-soluble cellulose derivate which is a reaction product of cellulose and urea. Cellulose carbamate which is miscible with xanthate solutions can be spun into fiber by wet spinning method. This is an economical process in accordance with Chinese production conditions.We comprehensively and systematically studied the changes of the structures and properties of cellulose in the process of cellulose activation and reaction by means of various techniques, including Fourier Transform Infrared Absorption Spectrum(FTIR) , Wide-angle X-ray Diffraction(WAXD) , Scanning Electron Microscopy(SEM) N Optical Microscopy -, Differential Scanning Calorimetry(DSC) N Kjeldahl Nitrogen Element AnalysisN Degree of Polymerization of Cellulose and Fiber Mechanical Property Measurement etc. After activated by sodium hydroxide, the cellulose had many changes of crystal structure. The lattice form converted from cellulose I to cellulose II,the crystallinity of cellulose decreased. The results revealed that the concentration of sodium hydroxide ^ the immersing time N air drying time diffierent cotton pulp etc. had effect on the degree of polymerization of cellulose. After electron beam (EB), the colour of the cellulose samples became yellow, finding >C=O in macromolecular chains. The degree of polymerization of cellulose decreased gradually with the increasing of irradiation dose, \vhich indicated that cellulose macromolecular chains degraded during EB irradiation. After steam explosion (SE), the cellulose showed volumn swellon,inter- and intra- molecular hydrogen bonds were destroied, the degree of polymerization of cellulose decreased. However, the cellulose crystal structure did not change. Byexamining the nitrogen content of cellulose carbamate the optimum processing conditions for synthesis of cellulose carbamate were determined. Through the correlation of the nitrogen content of cellulose carbamate and time, the reaction kinetic equations was established. The action mechanism of cellulose reaction with urea was also discussed. By the result from cellulose dissolvement photoes, the factors such as activation factors; synthesis factors and dissolvement factors were particular; discussed. The resulting solution is estruded into a precipitation bath to form cellulose carbamate and viscose filaments. The blend fibers have properties comparable with those of viscose fibers.