| Alginate is a naturally occurring linear polysaccharide found in all species of brown algae and some species of bacteria. It has many excellent advantages:being resource-rich, renewable, biodegradable and biocompatible, et al. In recent years, agiante has been extensively used as drug release materials, scaffolds for tissue engineering and medical dressing. However, the application and preparation of fibers from agiante are still in its underdevelopment stage.In this paper, we focus on the research and spinning appliance of high concentration sodium alginate solution (HCSA). The calcium alginate fibers were prepared by wet spinning of HCSA, combining with the investigation of the iquid crystalline property and rheological properties of the alginate. Moreover, the applied research of the alginate fibers were investigated.(1)Multivariate curve resolution was applied to 13C cross-polarisation magic angle spinning nuclear magnetic resonance (13C CP-MAS NMR) spectra of non-depolymerised alginate powders. The M/G ratios obtained from this method was compared with the traditional 1H solution state NMR method. It is concluded that 13C CP-MAS NMR in combination with multivariate curve resolution is a reliable, convenient (no sample preparation isrequired) and relatively rapid method for M/G ratio determinations of alginates and it may serve as a good alternative to the chemical techniques traditionally used.(2)The iquid crystalline property of the alginate was investigated using polarizing microscope (POM), X-ray diffraction (XRD), atomic force microscope (AFM) and rheometer. The results showed that the liquid crystalline of the alginate are probably lyotropic nematic liquid crystal.(3) The rheological behaviors of the HCSA were investigated by by using a rotational rheometer. The results also showed that the the HCSA solution behaved as non-Newtonian shear-thinning fluids, with the non-Newtonian index much higher than that of conventional SA solution (< 5 wt%). The influences of shear velocity and temperature on the Theological behavior of HCSA solution were also studied and the results showed that the activity energy of HCSA solution was changed and was lower than that of low concentration SA solution, indicating the liquid crystalline properties and spinnability of the HCSA. In addition, the influences of surfactant and alkali metal ions (Na+, K+) on HCSA were investigated. It is found that the addition of the surfactant and alkali metal ions can give a raise of the spinnability of the HCSA.(4) The calcium alginate fibe were prepared by wet spinning from HCSA. Based on the analysis of the influence factors in the spinning process on strength of fiber, the optimum spinning conditions were determined:the concentration of sodium alginate spinning solution isl2wt%,the concentration of coagulation bath is 7wt%calcium chloride,the temperature of spinning solution is 80℃, stretching ratio is 1.5. The best strength of the fiber can reach 7.74 cN/dtex.(5) The application of the alginate fibers were studied. Anano-microstructured porous carbon composite fibers consisted of NiO@C (or Co@C) were prepared by calcination of the nickel alginate fibers (cobalt alginate fibers) at 300-1000℃in high purity nitrogen. NiO and CoO nanoparticles were synthesized by calcination of nickel alginate fibers and cobalt alginate fibers at 300-1000℃in the air.
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