Preparation of polyynes organic-inorganic nanocomposites via in-situ synthesis: Structure, morphology and gas sensitivity

Inorganic nanoparticles SnO₂ and In₂O₃ were dispersed using an in situ synthesis technique in one of the polyynes polymer, namely poly-2, 5-dimethoxyethynylbenzene(PDMEB) to prepare organic-inorganic nanocomposites PDMEB/SnO₂ and PDMEB/In₂O₃. The nanocomposites were characterized by FT-IR, which highlighted the chain organization and the plasticizing effect of the nanoparticles on the polymers. Laser scanning confocal microscope (LSCM) images of the pristine polyynes and of their organic-inorganic nanocomposites, exhibited a growth of nanosized pores on glass substrates. The addition of inorganic nanoparticles clearly makes the pore distribution more uniform. The nanocomposites were deposited on quartz crystal microbalance (QCM) to study their sensitivity to various organic vapors, which showed high selectivity. PDMEB/In₂O₃ had high sensitivity to THF but PDMEB and PDMEB/SnO₂ had high sensitivity to alcohol (methane, ethane and isopropyl alcohol). In contrast, they had no sensitivity to acetone or chloroform.