Examples of additives are surface treated fumed silicas, for example TS-530 from Cabosil Corporation, with an 8 nanometer particle size and a surface treatment of hexamethyldisilazane; NA50HS silica, obtained from DeGussa/Nippon Aerosil Corporation, coated with a mixture of HMDS and aminopropyltriethoxysilane; DTMS silica, obtained from Cabot Corporation, comprised of a fumed silica silicon dioxid