Perfluoropolyether (PFPE) is a liquid substance, which possesses excellent oil-repelling property and chemical resistance. We have investigated the oil-repelling property of solid F/O emulsion with PFPE prepared by nonaqueous emulsification. When solid F/O emulsion, which is composed of hydrocarbon-type oil, wax, emulsifier, and PFPE, was applied on an artificial skin, the liquid film obtained did not exhibit oil-repelling property. This is because PFPE exists as stable droplets in hydrocarbon-type oil even after applied on the skin. In order to destabilize the droplets, the usage of perfluoroalkyl-type wax (perfluoroalkylether silicone, SFW) turned out to be effective. Although SFW formed a homogeneous liquid mixture with PFPE at the emulsification stage (85°C), it crystallized on the surface of the PFPE droplets after the solidification of the emulsion at room temperature. These encapsulated droplets easily broke down during the application to the artificial skin and PFPE separated successfully from hydrocarbon-type oil ; the applied film showed high oil-repelling property.
Conductive paints of polyaniline (PANI)/dodecyl benzene sulfonic acid (DBSA) composited with polystyrene (PS), polyester (PET) and polyurethane (PU) resin were prepared through a facile blending method. The extraction of PANI/DBSA from the aqueous reaction mixture was done by using a mixture of toluene and methyl ethyl ketone (MEK) (toluene : MEK=1 : 1 v/v). Then, the electrical, thermal stability and tensile properties of the prepared conductive PANI/DBSA composite films were evaluated. Almost all of the PANI/DBSA-PS, -PET and -PU composite films were found to possess relatively good conductivity and low surface resistivity for an electrostatic discharge (ESD) even at low PANI/DBSA content. Even when the PANI/DBSA content in the PANI/DBSA-PS and -PET composite was 2.5 wt%, the electrical conductivity and surface resistivity were found to be 3.92×10-4 Scm-1, 8.51×106 Ωcm-2 and 4.62×10-2 Scm-1, 7.22×104 Ωcm-2, respectively. Additionally these composite films exhibited good transparency. The highest conductivity (3.28×10-1 Scm-1) of the composite films was obtained when the PANI/DBSA content in PANI/DBSA-PS composite was 25 wt%. PANI/DBSA-PS composite film possessed the best thermal stability and the PANI/DBSA-PU composite films showed the lowest thermal stability of all evaluated samples. On the other hand, PANI/DBSA-PET composite films possessed the most elasticity when the PANI/DBSA contents were 10 and 20 wt%. However, PANI/DBSA-PU composite film possessed the most elasticity when the content was 5 wt%. PANI/DBSA-PS composite films possessed the lowest elasticity.