Synthesis, structural characterization and dielectric behavior of new oxime-cyclotriphosphazene derivatives

• Compounds synthesized for the first time.
• And investigated dielectric properties.
• Compared with each other.

The cyclotriphosphazene compound (2) bearing formyl groups as side groups was obtained from the reaction of 2,2-Dichloro-4,4,6,6-bis[spiro(2′,2″-dioxy-1′,1″-biphenylyl)]cyclotriphosphazene (1) with 4-hydroxy-3-methoxybenzaldehyde in the presence K2CO3 in tetrahydrofuran. Oxime-cyclotriphosphazene compound (3) was synthesized from the reaction of compound 2 with hydroxylamine hydrochloride in pyridine. The synthesized oxime-phosphazene compound (3) was reacted with alkyl and acyl halides. As a results, the cyclotriphosphazene compounds (1–10) bearing oxime ether and ester as side groups were obtained. The chemical structures of these compounds (1–10) were determined by elemental analysis, FT-IR, 1H, 13C and 31P NMR spectroscopic methods. Dielectric constant, dielectric loss factors and conductivity properties of cyclotriphosphazene compounds were measured over the frequency range from 100 Hz to 2 kHz at 25 °C and compared with each other. It is found that ester substituted cyclotriphosphazenes have higher dielectric constant. Our study suggests that these phosphazenes promising candidate materials in multifunctional optoelectronic devices.

The cyclotriphosphazene compounds containing oxime ether and ester as side groups (4–10) were synthesized. Dielectric constant, dielectric loss factors and conductivity properties of these compounds were investigated against frequencies (100 Hz–4 kHz) at room temperature and compared with each other. Oxime-cyclotriphosphazene compounds containing ester as side groups (7, 8, 9 and 10) have shown that the higher conductivity values than other cyclotriphosphazenes.Figure optionsDownload as PowerPoint slide