| 초록 |
The structures of (-OCH2CHR-) with R = CH2S(CH2)6SO2(CH2)8H (68MSO) or R = CH2SO2(CH2)14H (14SE) were studied via small angle x-ray scattering (SAXS), differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The SAXS and POM results for both 68MSO and 14SE at room temperature showed more highly ordered smectic phase (SmX) than smectic A or C. The Bragg peak in SAXS patterns of both of them indicated the smectic layer thickness which corresponded to twice the most extended side chain length. In other words, 68MSO and 14SE studied have bilayer structures, where side chains with all tran-conformation are normal to the main chain. The isotropization temperature (Ti ~ 148 ℃) of 14SE is much higher than that (Ti ~ 110 ℃) of 68MSO, indicating that the polar sulfone groups attached to PEO main chain in 14SE enhance the stability of bilayer structure and the hydrophilicity of PEO main chain. No Bragg peak in small angle region of 68MSO was observed above the Ti. However, broad scattering peak for 14SE was observed above the Ti, which might be related to the correlation hole effect induced by concentration fluctuation. |
