TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The hydrophobic agent comprises acrylonitrile, methyl acrylate, vinyl acetate and/or methylmethacrylate. The plasticizer comprises citrates, phthalates and/or lignosulfonates (preferably polyethylene glycol, propylene glycol, triethyl citrate, diethyl phthalate, dibutyl phthalate and/or dibutyl sebacate). The surfactant comprises sodium dodecyl sulfate (SDS), tri-n-octylphosphine (TOPO), triton X-100, cetyltrimethylammonium bromide (CTAB), cetyl trimethylammonium chloride (CTAC), and/or cetylpyridinium chloride (CPC).    TECHNOLOGY FOCUS - POLYMERS - Preferred Method: The carbon fibers are added to the mixture concurrently with formation of the polymer; or the carbon fibers are added to the mixture upon initiation of formation of the polymer. In the method, adding the carbon fibers involves dispersing the carbon fibers in a surfactant; milling the dispersed carbon fibers; and mixing the milled carbon fibers with the mixture concurrent with formation of the polymer. The method further involves casting the polymer nanocomposite on a substrate; and drying the polymer nanocomposite to form a polymer nanocomposite film. The method (M1) preferably involves forming a polymeric nanocomposite by: milling several carbon microfibers and carbon nanofibers dispersed in a surfactant to form milled hybrid carbon fibers; esterifying polyvinyl acetate to form polyvinyl alcohol (PVA) gel; adding the milled hybrid carbon fibers to the polyvinyl acetate prior to or concurrently with formation of the polyvinyl alcohol (PVA) gel; and adding a hydrophobic agent and a plasticizer to the PVA gel and hybrid carbon fibers to form the polymer nanocomposite. The hybrid carbon fibers are added to the polyvinyl acetate concurrently with formation of the polyvinyl alcohol (PVA) gel; or the hybrid carbon fibers are added to the polyvinyl acetate upon initiation of formation of the polyvinyl alcohol (PVA) gel. Esterifying polyvinyl acetate involves combining methanol, methyl acetate, and polyvinyl acetate to form a homogenous solution; and adding sodium hydroxide to the homogenous solution. Milling the carbon microfibers and carbon nanofibers includes ball milling. Preferred Components: The polymer or polymeric material comprises polyvinyl alcohol (PVA), polypropylene (PP), polyethylene (PE) and/or polyvinylidene fluoride (PVDF). The carbon fibers comprise carbon microfibers and/or carbon nanofibers (CNFs). The carbon microfibers have an average diameter of 2-12 mu m. The carbon nanofibers have an average diameter of 40-90 nm. The milled hybrid carbon fibers have an average diameter of 400-650 nm (preferably 500 nm). EXAMPLE - No suitable example given.