| Recently, with the rapid development of industry, people pay attention to environmental pollution and the more stringent environmental legislations have been made worldwide to reduce the emission of volatile organic compounds(VOC) into air. On this occasion, aqueous polyurethane dispersions have been extensively studied and applied in many fields. Many papers have reported that structure and properties of aqueous polyurethane dispersion were influenced by chemical structure and stoichiometric ratio of hard and soft segments. Up to now, the synthesis and study of functional polyurethane have been rarely reported in the previous literatures. The main works done and the result obtained in this thesis were as below:(1)Synthesis and research of an aqueous polyurethane- Disperse Blue-14 (PU-DB14)A novel polymeric dye of aqueous polyurethane disperse blue-14 was synthesized by our modified acetone process, which was characterized by the analysis of FTIR, UV-Vis spectroscopy, TEM:a. Fourier transform Infrared Spectroscopy(FTIR)was used to identify the structure of the polymeric dye, indicating an obvious carbonyl stretching absorption in disperse blue-14, which confirmed that disperse blue-14 had been bonded to the prepolyurethane.b. TEM(transmission electron microscope) made clear that the PU-DB14 has a unique shape resembling the leaves of bamboo.c. UV-Vis spectroscopy showed that there were two new absorption peaks appeared at 520nm and 765nm of the aqueous dispersions PU-DB 14.d. The effect of NCO/OH ratio on properties of PU-DB 14 film showed the tensile strength of the films increased with the increase of NCO content, the hardness of the films is harder, and the elongation at break decreased.(2) Synthesis and research of anti-bacterial aqueous polyurethanea. Fourier transform Infrared Spectroscopy(FTIR) indicated N, N- dimethyl ethanol amine had been bonded to the polyurethane, which had been made ammonium.b. The effect of anti-bacterial showed this material had anti-bacterial properties. The anti-bacterial effect of the PU emulsion increased with the increase of amine content.c. TEM made clear that the anti-bacterial polyurethane has an approximately sphericity shape and dispersed symmetrically. And the mechanical intensity of this material is good.(3) Synthesis and Properties of Anti-static PolyurethaneA novel material was synthesized by polyurethane-polyaniline composite, which was characterized by the analysis of FTIR, TEM, thermogramitry analysis (TGA), DSC. The results indicated that tensile strength and thermal stability of the material were increased. The polyurethane-polyaniline composite can be used as coating materials with anti-static properties. The relation of volume resistance and PAni content was also been studied:a. The volume resistance of PU/PAni film decreased with the increase of PAni, when the content of PAni is 5ï¼…, the volume resistance of this material is enough to use for anti-static coating.b. The spectroscopy of FTIR showed that the NCO of PU fully react with NH of Pani, and formed reticular or cross-link configuration.c. The mechanical properties and heat resistance were improved by introducing PAni into the PU chain.d. TEM of Polyurethane-polyaniline made clear that there was a bulge which was polyaniline crystal.
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