| Solid polymer electrolytes (SPE) have many advantages such as: light weight, easier to fabrication, good viscoelasticity and thermal stability. They have potential applications in solid state secondary lithium batteries, fuel cells, elecrtochromic display devices, electrochemical sensors, capacitors and so on. Researches on SPE have received considerable attention from people. The crucial part of the reasearch on SPE material is the design and synthesis of the polymer matrix, which can complex with the alkali metal positive ion, and provides the passageway for the ionic migration. In this paper, five new sorts of crown ether polymer matrixes were designed and synthesized, which complex respectively with lithium perchlorate (LiClO4), and form SPE. For these synthesized SPE, we studied their chemical structure, microscope morphology, thermal stability and ionic conductivity. This paper consists of six parts as follows:1. For SPE, the developing history, the categories, ion-transport mechanism, technique of characterization, and the methods to raise the ionic conductivities of polymer electrolytes were reviewed. Some prospects on the future SPE research were also discussed. To expound the basis of this thesis topic. 338 references were quoted.2. According to ionic conduction mechanism and the theory of host-guest supramolecular assemble, a novel series of Schiff base type crown ether polymers were synthesized for the first time by solution polycondensation of diformy-dibenzo-14-crown-4 and diamine, which complex with LiClO4 and prepare the SPE. The polymer matrix and its Li+ complexes were characterized by FT-IR. The results show that the synthesized products are consistent with designs. Thermal stability of all polymers is indicated better by using thermogravimetry(TG) and differential thermal analysis(DTA). SEM, TEM and XRD were used to investigate superficial morphology and microcosmic structure. The results indicate supramolecular assemble is existential in SPE molecular, the layer upon layer of the crown ether ring can form ionic passageway. A.C. impedance spectra were measured at room temperature. According to analysis and calculating of the imitated equivalentcircuit, the conductivity optimum value is 10-7 s/cm. The relation between conductivity and temperature of all the electrolytes has been exhibited to follow the Arrhenius equation. An imitating equivalent circuit is proposed in this paper, according to the device structure. A.C. impedance test conductance, which can imitate the data better, and has certain general suitableness.3. By the solution polycondensation method, a new series of sulphonamide type crown ether polymers wrer prepared for first time, which complex as matrix with LiClO4 and get novel SPE. The chemical structure of polymers was characterized by FT-IR. Superficial morphology and model of molecule accumulation were observed by SEM and TEM. X-ray diffraction analysis proves that the kind of SPE is amorphous, and it is helpful for ionic conductivity. The results of the thermal analysis indicate that they have better thermal stability. The ionic conductivity maximum can get to 10" s/cm at room temperature. The conductivity increases with the increase of temperature, abide the Arrhenius equation.4. A series of ketone type crown ether polymers were synthesized for the first time by the polyphosphoric acid catalysis reaction of dibenzo-14-crown-4, and dibasic acids. The ketone type crown ether polymer, used as matrixes, complex with lithium perchlorate(LiClO4), and prepare a series of novel solid polymer electrolytes prepared. Fourier transform infra-red spectroscopy (FT-IR) was used to investigate chemical structure. The superficial morphology and microscope structure of the polymers were observed tlirough the scanning electron microscopy (SEM) and transition electron microscopy (TEM). X-ray diffraction spectra show the SPEs are amorphous, and it is favorable for the ionic conductivity. This kind of SPE has better thermal sta...
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