Abstract
Synthesis of linear polymer/zeolite nanocomposites under high pressurePolymer/zeolite nanocomposites form a class of materials constituted by polymer chains inside the pores of the zeolite (porous materials with a framework principally built up of SiO4 tetrahedra). Confinement in the microporous material allows reactive polymers to be stabilized, opening the way for the exploitation of their electrical and optical properties. The insertion of monomers in the zeolite takes place in a diamond anvil cell under high pressure, which induces polymerization (monitored by infrared spectroscopy) without any external assistance, avoiding the use of unwanted catalysts. The use of a zeolite host with unidirectional porosity, unlike previously investigated three-dimensional pore systems zeolites, can induce the formation of linear polymers with useful directional properties. In this work, we studied the synthesis of polyacetylene/TON and polycarbonyl/TON composites, as the linear polymers fit in the unidirectional 5.7x4.6 Å micropores of TON (Theta-1, ZSM-22).Characterization by X-ray diffraction allowed us to perform structure refinements of nanocomposites by the Rietveld method and to locate the polymer using difference Fourier maps, which also provide information on the number of chains by unit cell. There are 4 in the case of polyacetylene and 1 for polycarbonyl. DFT calculations were performed for TON, polyacetylene/TON and polycarbonyl/TON to predict their physical properties: transition from an insulating to a semi-conducting or metallic state.