Study Of Magnetic Chitosan Composite

Under the effect of the extra magnetic field, magnetic materials can form the mechanical effect and thermal effect, and this is the idea headspring of this thesis. In this thesis, magnetic chitosan composite were prepared via two methods, also added magnetic field to control the inorganic fillers in the chitosan matrix.1. Preparation of magnetite/chitosan nanocomposite via in situ compositing methodIn-situ compositing method was used to prepare magnetic chitosan rod by using chitosan membrane as template and NaOH as precipitant. Layer structure of the magnetic chitosan rods was observed from the digital photos, the SEM images showed the micro layer structured of the rods at the same time, the mechanism for preparing the rods was discussed in detail. From the TEM images it can be concluded that the size of Fe₃O₄ particles was about 15nm, and dispersed well in chitosan matrix. X-ray diffraction analysis results demonstrate the formation of magnetite in the chitosan matrix. From the magnetic measurement, it could be concluded that the magnetic chitosan rods were super-paramagnetic. Mechanical properties of the magnetic chitosan rods were measured. From magnetic measurement it can concluded that the as-prepared magnetite is super-paramagnetic.2. Preparation of magnetite/hydroxyapatite/chitosan rods via in-situ precipitation.The magnetite/hydroxyapatite/chitosan rods were prepared by blending magnetic hydroxyapatite with chitosan via in-situ precipitation. Magnetic hydroxyapatite was obtained by co-precipitation method. X-ray Diffraction (XRD), size distribution and magnetic measurement were performed to characterize the as- prepared magnetic hydroxyapatite. It could be also concluded from the three point bending test that the mechanical properties improved as the inorganic content decreased. The microstructure of magnetic hydroxyapatite/chitosan rods were carried out by scanning electron microscopy (SEM).3. Preparation and characterization of magnetite/hydroxyapatite/chitosan nano-composite by in-situ compositing methodThe chitosan /hydroxyapatite /Magnetite nano-composites were prepared viain-situ compositing by preparing precursor solutions and models with chitosan membrane; also this method solved the problem of the nano-sized particles aggregation in polymer matrix. These nano-composites were characterized by chemical, spectroscopic, magnetic, mechanical and morphological methods. Comparison of the X-ray diffraction patterns and FT-IR spectra of the nano-composites with those of pure components revealed that the formation of hydroxyapatite and magnetite. Transmission Electron Microscope results showed that the size of as-prepared inorganic particles was under 100 nm, and dispersed homogeneously in the chitosan matrix. Scanning electron microscopy (SEM) was carried out to investigate the microstructure of CS/HA/Fe3O4 composite. From the magnetic measurement, it could be concluded that the nano-composites were super-paramagnetic. Mechanical properties of CS/HA/Fe3O4 composite rod are much better than that prepared via traditional method. 4. The orientation of inorganic fillers in chitosan matrixMagnetite/chitosan nano-composite was prepared via in-situ compositing in the magnetic environment. From the XRD, TEM testing results, it can be concluded that nano magnetite particles arranged orderly in the chitosan matrix. Also, the method of in situ hybridization was explored to prepare CS/HA/magnetite nanocomposite in the magnetic environment, and from the TEM images it can be concluded that the inorganic fillers were oriented.