| 초록 |
A new diamine containing phosphine oxide and thioether bonds was prepared via the Grignard reaction to dichlorophenylphosphine oxide with 4-fluorophenylmagnesium bromide, followed by an aromatic substitution reaction with 4-aminothiophenol. The polyimides (PIs) were derived from diamine containing phosphine oxide moiety and several aromatic dianhydrides such as 4,4’-[p-thiobis(phenylenesulfanyl)]diphthalic anhydride (3SDEA), 4,4’-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) 4,4-oxydiphthalic anhydride (ODPA) and and pyromellitic dianhydride (PMDA) by the conventional two-step polycondensation. The characterization of new diamine was confirmed by 1H, 13C NMR, FT-IR. The PIs were measured thermal properties and thermo-mechanical property using TGA, DSC and DMA, and optical properties utilizing UV-vis spectra and prism coupler. All of the PIs exhibited good thermal stability, including high thermal decomposition temperatures (>500 °C), glass transition temperature (Tg) in the range of 212-295 °C. Partichlarly, PI based on 3SDEA showed good optical properties, such as optical transparency higher than 80% at 450 nm at a thickness of about ca. 10 μm and high refractive index (1.725) with low birefringence (0.0087) due to the heavy atom effect of the high sulfur and phosphorous contents. |
