Polybenzimidazole Compounds, Polymeric Media, And Methods of Post-Polymerization Modifications

A PBI compound includes imidazole nitrogens at least a portion of which are substituted with an organic-inorganic hybrid moiety. At least 85% of the imidazole nitrogens may be substituted. The organic-inorganic hybrid moiety may be an organosilane moiety, for example, (R)Me2SiCH2- where R is selected from among methyl, phenyl, vinyl, and ally!. The PBI compound may exhibit similar thermal prop­erties in comparison to the unsubstituted PBI. The PBI compound may exhibit a solubility in an organic solvent greater than the solubility of the unsubstituted PBI. The PBI compound may be included in separatory media. A substi­tuted PBI synthesis method may include providing a parent PBI in a less than 5 wt % solvent solution. Substituting may occur at about room temperature and/or at about atmo­spheric pressure. Substituting may use at least 5 equivalents in relation to the imidazole nitrogens to be substituted or, preferably, about 15.