Abstract
Summary: Rigidโflexible polyethers consisting of terphenyl and aliphatic segments of various lengths along their main chains and disubstituted by dendritic wedges of various generations (G~0~, G~1~, and G~2~) are examined in their bulk states. Characterization of phase transitions has been performed by means of differential scanning calorimetry (DSC) and was supported by structural information obtained from smallโangle light scattering (SALS) and polarized optical microscopy (POM) experiments. In order to characterize order on the molecular size scale, twoโdimensional (2D) wideโangle Xโray diffraction (WAXS) experiments have been performed for macroscopically oriented samples. All results pointed out a highly ordered nature of these materials. Both monomers and polymers were characterized. In the case of polymers, structures consisting of layered backbone sheets separated by the side dendritic moieties filling the space between them were deduced. In all cases, strong effects of molecular parameters, such as main chain flexible spacer's length and sizes of substituents, on transition temperatures (oddโeven effect), degree of orientation, and distances characteristic for the supramolecular structures, were observed.
Example of 2D Xโray diffraction patterns recorded for oriented films of the polymers PETHโ(2OC~12~H~25~) (the zero generation).
magnified imageExample of 2D Xโray diffraction patterns recorded for oriented films of the polymers PETHโ(2OC~12~H~25~) (the zero generation).