SYNTHESIS AND THERMAL ANALYSIS OF AROMATIC POLYSULFIDE HAVING PHOSPHINE OXIDE GROUPS

Abstract

An aromatic polysulfide was synthesized by the reaction of bis(4-fluorophenyl)phenylphosphine oxide (BFPO) with potassium salt of biphenyl-4, 4′-dithiol (BPDT) in the presence of 18-crown-6. In order to establish the characteristics of polymerization, reaction conditions such as the temperature and the time were changed. The polymerization in N-methyl-2-pyrrolidone (NMP) at 155°C gave the polysulfide having inherent viscosity of 0.71 dl/g(_??_w=6.8×10⁴). An X-ray diffractogram of the polysulfide indicated a typical halo pattern, suggesting that it was amorphous. The thermal properties of the polysulfide were studied by differential scanning calorimetry (DSC) and thermogravimetry (TG). The glass transition was observed in DSC at 232°C. TG measurements showed the onset of thermal decomposition in nitrogen at 480°C, and its activation energy was 158kJ/mol.