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Greenhouse effect, air pollution and water pollution and other environmental problems are becoming increasingly attracted people's attention. In recent years, developed countries, environmental governance, has begun pollution from passive towards the development of new production processes and technologies to reduce pollution sources and production of environmentally friendly products. \To pollution-free supercritical fluid instead of conventional organic solvent preparation and purification of various products caused researchers are highly valued. Supercritical fluid technology is a new chemical engineering technology, because of their special physical and chemical properties, in the field of chemistry is widely used. Nano-materials research has become popular in today's high-tech in a field is a function not only of its own material, but also for new functional materials and development of composite demonstrated broad application prospects, and thus in materials, chemical, biological and medical has been widely applied. Supercritical fluid (SCF) is applied to nanofabrication last decade developed a new technology, SCF technology to prepare superfine powder with high purity, geometry, uniform, small particle size, narrow particle size distribution, manufacturing process is simple, lower operating temperature and apply a wide range of materials, etc., it has been of concern. This thesis is centered on supercritical carbon dioxide nanoparticles synthesized, for the following studies: 1. Synthesized a series of two kinds comprising a non-polar hydrocarbon tail, similar to the structure of the surfactant AOT n-butyl succinate sodium (DBSS), succinic acid di-n-amyl sodium (DPSS), Amber di-n-hexyl ester sulfonate (DHSS) and succinic acid di-n-octyl sulfonate (DOSS), and use 1 H NMR and elemental analysis by means of surfactants were characterized to determine the synthesis The optimum conditions. Such surfactants are investigated in supercritical carbon dioxide (scCO 2 ) and fluorocarbons 1,1,1,2 - tetrafluoroethane (HFC-134a) the solubility and phase behavior, The effects of system temperature and pressure on the surfactant in scCO 2 and HFC-134a in the physical and chemical properties of the investigated surfactant type and its use in scCO 2 and HFC-134a in the relationship between the physical and chemical properties. The results show that the hydrocarbon surfactant solubility in HFC-134a is relatively large. In scCO 2 and HFC-134a in the solubility increases with pressure, the increase of the temperature. In scCO 2 medium solubility with hydrocarbon chain of the surfactant increase in the number of carbon atoms increases, the solubility in HFC-134a as the surfactant hydrocarbon chains increase in the number of carbon atoms reduced. 2. By esterification reaction and the sulfonation reaction in an organic solvent two-step synthesis of a series of fluorine-containing structures similar AOT anionic surfactant bis (3,3,4,4,5,5,6,6,6 - Nine fluoro-1 - hexyl) -2 - sodium (di-HCF5), bis (2,2,3,4,4,4 - hexafluoro-1 - butyl) -2 - sodium (di-HCF3 ), bis (2,2,3,3 - tetrafluoro-1 - propyl) -2 - sodium (di-HCF2) and bis (2,2,3,3,3 - pentafluoro-1 - C yl) -2 - sodium (di-CF2), and by elemental analysis and
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