Synthesis and properties of poly(1,3-dialkoxybenzene)s from facile solvent-free grinding oxidative coupling polymerization

Abstract

Soluble conjugated aromatic poly(1,3-dialkoxybenzene)s were obtained in high yield up to 80% in 30 min by grinding 1,3-dialkoxybenzene with anhydrous FeCl 3 powder in a mortar at ambient and solvent-free condition. The polymers were characterized by FT-IR, 1 H-NMR, 13 C-NMR, and gel permeation chromatography. The structure of the aromatic rings linkage at meta-position was confirmed. Thermogravimetric analysis, UV-Vis, fluorescence spectroscopy, and four-probe a.c. technique were used to probe the thermal, optical, and electrical properties of the polymers. The polymers displayed high thermostability with the decomposition temperatures at about 382-388°C. The optical energy gap (E g ) of the polymers was 4.23 eV and electrical conductivity at room temperature was 10 -6 S cm -1 . The fluorescence curve of the polymers displayed the maximum at 344 nm in CH 2 Cl 2 solution. The morphology of the polymers was determined by X-ray diffraction and scanning electron microscope technique.