Elemental analysis (C, H, N) was carried out with a Perkin–Elmer C, H, N analyser model 2400 using acetanilide as reference. Molecular weight of polymer was obtained by gel permeation chromatography (GPC) with an ALLIANCE 2695 WATERS chromatographer with an UV WATTERS 2998 (Photodiode Array Detector) detector and two PLgel MIXED C lineal columns. Tetramethylsilane (TMS) was used as internal reference and samples were prepared with CDCl 3 as solvent. Nuclear magnetic resonance (NMR) spectra were recorded with a Varian nuclear magnetic resonance 400 MHz spectrometer and it was operated at 400/100 MHz for 1H and 13C NMR respectively. 4-biphenylmethanol was employed as received.įT-IR spectra were acquired with a Perkin-Elmer Frontier spectrophotometer with a spectral resolution of 4 cm −1, samples were prepared as pellets with anhydrous KBr. 2,2ʹ-azobisisobutironitryle (AIBN) and benzoyl peroxide (BPO) were recrystallized in methanol. Tetrahydrofurane (THF) was distilled and dried with metallic sodium and benzophenone under argon atmosphere. ![]() Pyridine was distilled and dried over KOH under argon atmosphere. Acryloyl chloride was purified by distillation in presence of hydroquinone. Reagents and solvents employed for the synthesis of monomer and polymers were purchased from Sigma-Aldrich Company. Further, the polymer is highly soluble in different organic solvents and it can be obtained by solution or bulk polymerization techniques. This polymer exhibits fluorescent emission in the range of 300 to 550 nm and wide band gap. ![]() Taking account this background, in this work we report the synthesis and characterization of a polyacrylate with biphenyl pendant groups. However, these polymers do not have any application until now. Previous works have reported the study of the spacial order in polymers containing biphenyl pendant groups. These groups contain conjugated aromatic rings connected by single C-C bonds with free rotation, which increase the value of band gap. An alternative for the obtaining of organic short-wavelength emitters are materials with biphenyl and terphenyl groups. Some examples of organic materials containing fluorene groups with emission around 400 nm have been reported recently. However, there is not much report about satisfactory materials for UV and violet light emitters. Also, heterocyclic moieties with fused rings like carbazole, quinoline and dibenzothiophene have been employed to obtain organic blue light emitters. Highly efficient blue-light organic emitter materials like polymers, oligomers and compounds are typically based in conjugated structures containing fused rings, e.g., naphthalene, anthracene, pyrene and fluorene moieties. Thus, it is necessary to design novel organic materials with UV-Blue emission. Despite poly( p-phenylenes) are still the most employed organic materials for short-wavelength emitters, they exhibit poor solubility in organic solvents and they are difficult to process. ![]() This implies the design of non-planar conjugated structures. To achieve the wide band gap it is necessary to confine the extent of conjugation imposing constraints in the molecular size or introducing a twist between conjugated rings. ![]() Some properties required for this are wide band gap, high quantum yield, high solubility and capability to form films with controlled morphology. However, it is difficult to obtain appropriate materials to fabricate OLEDs with efficient emission of UV or blue light. Further, short-wavelength emitter materials are interesting for construction of high density information storage devices. The short-wavelength radiation from solid state sources it is important for the construction of full colour displays because different phosphors can be excited by UV, violet or blue light to obtain light with higher wavelengths.
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