New aromatic−aliphatic polyethers containing alkyl- or alkoxy-substituted oligophenyl units were synthesized. The polyethers were characterized by viscosimetry, gel permeation chromatography, thermal and mechanical analysis, NMR, and UV−vis luminescence spectroscopy. The type of the side chain as well as the length of the flexible spacer influence the thermal and mechanical behavior of the synthesized polyethers. In all examined cases, the isotropization transition as well as the glass transition temperature show an odd−even effect depending on the spacer segment length. The polymers are soluble in common solvents and form free-standing films that combine high modulus (E‘) at room temperature with blue photoluminescence. High fluorescence quantum yield (φ = 0.82) was obtained for the polyethers studied, which is comparable to values reported in the literature for substituted poly(p-phenylenes). The type of the substitutent affects the maximum of the fluorescence peak, which is in the range 370−430 nm.

New blue luminescent polyethers were prepared by interfacial polymerization of 2,5-diphenyl-, 2-biphenyl-, and 2,5-bis(biphenyl)hydroquinone diacetates with α,ω- dibromides. These polymers were soluble in common solvents, show liquid crystallinity in some cases, and can be melt processed at relatively low temperatures where they are thermally stable. Moreover their solid structure and corresponding properties (e.g. optical) can be controlled by judicious choice of the monomer unit. The synthesized polyethers were characterized by viscosimetry, gel permeation chromatography, thermal analysis, mechanical analysis, and UV−vis luminescence spectroscopy. The polymers show blue photoluminescence and have relatively low liquid crystalline transition temperatures, or they are amorphous depending on the symmetry of the substitution. The photoluminescent maxima were in the range 390−407 nm depending on the monomer structure. Free standing films were casted from solutions for some polymers, and in one case the mechanical properties were examined.

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A series of rigid aromatic polyesters containiig substituted oligophenyls wasprepared. Aliphatic and aromatic side groups were used to increase the solubility. New oligophenyldiols were synthesized by coupling aromatic Grignard reagenta with aromatic halides, using palladium complexes as catalysta. The polyesters were prepared by melt polycondensation and characterized by viscosimetry, thermal analysis, and dynamic mechanical analysis. The temperature dependence of the intrinsic viscosity, in the range 30-85 O C , was sensitive to the type and position of the side groups. Polyesters with aromatic substituents were stable up to 400 "C. The glass transition temperatures of the polyesters with aromatic side groups were in the range 150-250 "C. Dynamic mechanical analysis showed that in the cases where aromatic Substituents were used to increase solubility, the obtained polymers appear to have useful mechanical properties at high temperatures. The glass transitions appeared in the range 160-220 "C, while a plateau modulus in the range of 108 Pa was obtained at high temperatures (up to 350 O C ) .