Preparation Of Several Kinds Of Oil-soluble Metallic Nanoparticles And Investigation Of Their Tribological Behavior

The following three aspects are included in this thesis:1.Preparation and characterization of oil-soluble Sn nanoparticles modified by O,O'-dioctyl dithiophosphinic acid(C₈DDP) and bis(2-ethylhexyl)phosphate(or tri-n-octylphosphine oxide,TOPO)Surface-modified Sn nanoparticles were prepared via chemical reduction of aqueous CuSO₄ by sodium borohydride in the presence of O,O'-dioctyl dithiophosphinic acid(C₈DDP) and bis(2-ethylhexyl)phosphate(or tri-n-octylphosphine oxide) as the modifing agents.The morphology and structure of the as-prepared nanoparticles were characterized by means of Fourier transformation infrared spectrometry(FT-IR) and transmission electron microscopy(TEM).Results indicate that the as-synthesized Sn nanoparticles can be well-dispersed in organic solvents such as petroleum ether,liquid paraffin,chloroform,benzene,and toluene, and they have a uniform size.Moreover,the surface modified Sn nanoparticles as a lubricating oil additive showed good antiwear and friction-reduction properties at low and medium loads.2.Preparation and characterization of oil-soluble Bi nanoparticles modified by O,O'-dioctyl dithiophosphinic acid(C₈DDP)Oil-soluble surface-modified bismuth nanoparticles were prepared via reducing aqueous bismuth salt by sodium stannite in the presence of O,O'-dioctyl dithiophosphinic acid as the modifying agent.The as-prepared bismuth nanoparticles were characterized by means of Fourier transformation infrared spectrometry(FT-IR) and transmission electron microscopy(TEM).Results show that the oil-soluble Bi nanoparticles can be dispersed in organic solvents such as benzene,toluene, chloroform,liquid paraffin,and petroleum ether,and they have a uniform grain size.At the same time,the surface-modified Bi nanoparticles as a lubricating additive possessed excellent friction-reduction and antiwear properties.3.Preparation and characterization of oil-soluble Cu nanoparticles modified by alkyl salicylic acidOil-soluble surface-modified Cu nanoparticles were prepared via reducing aqueous copper sulfate by hydrazine hydrate in the presence of alkyl salicylic acid as the modifying agent.The as-prepared copper nanoparticles were characterized by means of Fourier transformation infrared spectrometry(FT-IR) and transmission electron microscopy(TEM).Results show that the oil-soluble copper nanoparticles can be dispersed in organic solvents such as benzene,toluene,chloroform,liquid paraffin, and petroleum ether,and they have a uniform grain size.At the same time,the surface-modified copper nanoparticles as a lubricating additive possessed excellent friction-reduction and antiwear properties.