| Summary: | 碩士 === 臺灣大學 === 高分子科學與工程學研究所 === 95 === In this study, we successfully synthesized polymer/iron oxide nanowires (NWs) by surface-initiated atom transfer radical polymerization (surface-initiated ATRP). Fe3O4 nanoparticles (NPs) were first prepared by co-precipitation method. As-prepared Fe3O4 NPs were then dispersed in NaOH aqueous solution and sealed into Teflon-lined stainless steel autoclaves. By changing reaction temperature、reaction time、concentration of NPs、concentration of NaOH and capacity, we could obtain different product which TEM and SEM were used to investigated the morphology and X-ray powder diffraction to characterize. Under apropos condition, Fe3O4 NWs were successfully synthesized. In order to grow polymer from the surface of Fe3O4 NWs by surface-initiated ATRP, we design a molecule-(2-bromo-2-methylproponate) octyl phosphonic aicd (P8CBr) which one end has phosphonic aicd and the other can be used as an ATRP initiator. P8CBr can therefore be linked to the surface of Fe3O4 nanowires via phosphonic acid which can be verified by Fourier Transform Infrared spectroscopy (FT-IR). P8CBr/Fe3O4 can be seen as an initiator and we use CuBr/PMDETA as a catalyst. Adding DMF as solvent is in order to improve the derpersibility of initiator in monomer (styrene). Polystyrene (PS) was then grown from the surface of iron oxide at 100oC. The reactions continued for 6 hr and 24 hr. The TEM were used to observe the morphology of product and GPC was used to obtain the number average molecule weight of grown PS. Besides, the stability of P8CBr/Fe3O4 and PS/iron oxide in chloroform was tested by centrifuge and compared by ultraviolet-visible (UV) absorption spectroscopy. The magnetic property of Fe3O4 NPs、Fe3O4 NWs and PS/iron oxide were measured by superconducting quantum interference device magnetometer (SQUID magnetometer).
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