The Preparation Of Calcium Alginate/inorganic Nano Composite Fiber And Performance Research

Developing bio-polymer based fibers is an important project in the future. Alginate is a natural polymer which extracted from brown algae, seaweed and other marine algae. It has been considered as the most promising biomaterial owing to its biocompatibility, non-toxicity, wide renewable resource and other excellent features. The preparation of calcium alginate/inorganic nano-composite fibers and the influence of nano-silica and MMT on the mechanical performance of composite fibers were investigated in this thesis.Nano-silica and MMT were used to modify the alginate fiber. The effects of nano-particles on the rheological properties of spinning solution were analyzed. Sodium hypochlorite liquid was added to the spinning solution, and the degradation experiments were conducted. It was observed that the viscosity of the spinning solution was stable within a certain time in the fiber preparation process. This avoids yielding fibers with significantly different properties caused by the different flowing properties of spinning solution.Pure calcium alginate fibers and nano-silica/calcium alginate fiber were prepared by wet spinning equipment respectively. The fiber strength test, TG test results show that the strength of fibers is greatly improved because of the existence of nano-silica. The surface morphology of the fibers was investigated by SEM. According to the test results, the best proportion of nano material was established.The dispersability of MMT in composite spinning solution was tested through polarized light microscopy and TEM. The results showed that the MMT occurred exfoliation. The composite fibers were prepared by wet spinning, and its thermal property was tested by TG and DTG. The results showed that the thermal stability of the composite fiber was improved because of the existence of MMT. MMT acts as the isolation layer in the fibers, so that the fiber has good heat resistance. The strength of fibers also was improved. The strength data were analyzed according to TEM images. The SEM images of composite fibers showed that the fiber surface was very smooth, there is no damage on the surface morphology.