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A series of six conjugated aromatic polyazomethines has been obtained by high-temperature solution polycondensation of diformyltriphenylamine with different primary aromatic diamines. The structures of polymers are characterized by means FTIR, 1H NMR, and 13C NMR spectroscopy and elemental analysis; the results show an agreement with the proposed structure. Polyazomethines emitted blue or blue-green light. Relative PL intensity of the polymers investigated in chloroform solution was found about 0.30%, while for doped ones it was about 20% in relation to 9,10-diphenylanthracene. Additionally, the photoluminescence spectra of the polyazomethines in polymer blend with poly(methyl methacrylate) (PMMA) have also been described. The lowest optical band gap value at 2.41 eV was detected. Polymers were investigated also by cyclic voltametry and differential pulse voltammetry in dichloromethane. An influence of different types of dopants, i.e., methanesulfonic acid (MSA), camphorsulfonic acid (CSA), m-cresol (MC), p-chlorophenol (PC), and p-pentadecylphenol (PDP), on absorption and emission wavelengths was investigated.

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The blends of thermoplastics with liquid crystalline polymers show, in general, poor properties because of the lack of adherence between the two phases. The use of ad hoc synthesized copolymers containing the monomer units of the two polymers has been recently considered by some of us for blend compatibilization, and the results appear promising. In this work, new PE‐g‐LCP copolymers, prepared either by the synthesis of the LCP in the presence of a functionalized PE, or by reactive blending of the latter polymer with preformed LCP, have been employed as compatibilizing additives for blends of PE with a semirigid LCP. The morphology and the rheological and mechanical properties of the ternary blends, compared with those of samples without compatibilizers, or containing conventional maleic anhydride grafted PE, indicate that the PE‐g‐LCP copolymers do in fact lead to an improvement of interfacial adhesion, both in the melt and in the solid state, as well as to a modest enhancement of the mechanical properties. The results may be rationalized considering that the PE‐g‐LCP copolymers used by us consist of fairly short PE backbones with LCP grafts of various length. The molecules with longer LCP branches are thought to become mixed at the surface of the LCP particles and to give rise to fairly weak interaction with the PE matrix. It is argued that new PE‐g‐LCP copolymers synthesized from higher molar mass functionalized PE samples might show much better compatibilizing performance.