Organic vapors are additional pervious than permanent gases within the composite membranes, with solvent and resolving permeability being concerning orders of magnitude beyond permanent gas permeableness. Gas and vapor transport properties were studied in mixed matrix membranes containing elastomeric ethylene-octene polymer (EOC or poly(ethylene-co-octene)) with 3 styles of carbon fillers: virgin or modify multi-walled carbon nanotubes (CNTs) for the open-chain organic compound (hexane), hydrocarbon (toluene), alcohol (ethanol), likewise as water for the representative samples. Gas permeableness of EOC lies between that of the additional pervious PDMS and also the less pervious semi-crystalline polythene and plastic. The results of the carbon-filled membranes supply views for application in gas/vapor separation with improved mechanical resistance.