| 초록 |
Recently, a number of groups have reported organic-inorganic hybrids as one of candidates to improve the permeation characteristics. At least, two effects of inorganic particles in polymer matrix on permeation properties can be described. First, the strong interaction between polymer and inorganic particle reduces segmental and subsegmental mobility and inhibits segmental packing of polymer. A change in polymer structures contributes to increase diffusivity (by disrupting interchain packing) and diffusivity selectivity (by increasing polymer backbone stiffness), which plays more important role than solubility in determining the productivity of given polymers. The fact that a polymer with a high glass transition temperature and a large interchain spacing shows high permeability/selectivity properties is consistent with the conclusion of Robeson and many other structure/property studies. Second, the interaction between the residual OH groups on the inorganic component and polar gases (such as CO2 and SO2) and the morphological changes can give rise to the increase of solubility associated with an increase of the Henry's contribution. In the present study, we explore gas transport properties of PEBAX -silica hybrids. These composites have been prepared via in situ polymerization of tetraethoxysilane (TEOS) using the sol-gel process. The permeability and permselectivity at various temperatures were obtained for He, CO2, O2 and N2. It is our intention to investigate and discuss the effect of silica incorporation into PEBAX on the structural changes and corresponding permeation properties.
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