| Summary: | 碩士 === 國立臺灣大學 === 化學研究所 === 89 === Abstract
Nano-composites and nano-porous materials were prepared from ionic polymer and metal oxide precursors by sol-gel methods. The ionic polymers were the derivatives of polystyrene, and the metal oxides were silica and titania. The interaction between the organic and inorganic component was varied depending on the functional groups on the polymers such as ammonium ion, sulfonate ion, and diol. The ratio of the organic/inorganic composites was also varied to determine the optimal condition for synthesis.
Nano-composite was prepared when the polymer content in the composite was greater than metal oxide. Different methods were compared in order to find the best way in synthesis of nano-composite. The properties of the composites were characterized by elemental analysis, TGA, DSC, 1H-NMR, and GPC. The thermal properties of the nanocomposites were different from the polymer itself. The glass transition temperature (Tg) of the copolymer, polystyrene-poly-4-vinylbenzyl chloride, was lower than pue polystyrene. On the other hand, the Tg of the composite increased with the introduction of metal oxide and the amount of ionic functional groups on the copolymer.
Nano-porous material was prepared when the polymer content in the composite was less than metal oxide. The organic component was removed by calcination to leave the porous structure. N2 adsorption-desorption isotherm, XRD, SEM, TGA, EA, NMR was used to character the properties of the nano-porous material. The polymers were used as shape-directing agents and addition of small organic molecule as co-templates was also examined. It was found that the porosity was sensitive to the pH of the synthesis gel, the temperature of hydrothermal process, and the addition of small organic template. Porous metal oxides with both meso- and micro- pores were obtained.
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