Fe₃O₄ ／Polyaniline–polyacrylonitrile Composite Nanofibers Prepared By Microemulsion Polymerization And Electrospinning

Conductive polymers compounded with nano-inorganic composite have attracted a great deal of attention in recent years. The obtained composite materials have the superior properties as both conductive and other properties, such as magnetic properties. Nanoinorganic particles are usually coated by polymers to prevent the nanoparticles from agglomerating due to their high surface activity. The nanoinorganic Fe₃O₄ particles adopted in this article is a kind of important anti-spinal ferrite, one of the most widely used soft magnetic materials. And PANI is one of the commonly used conductive polymers because of its excellent conducting performance, good environmental stability, cheaper material costs, and unique doping mechanism. It can also be easily synthesized and has a high production rate and diverse molecular structures, etc. Organic-inorganic hybrid materials exhibiting both electric and magnetic properties are very useful for electromagnetic shielding and microwave absorption. For Pan, a serious matter in application is its poor processability resulted from its insolubility and infusibility. Nano-conducting polymers have become a focus in recent years; in that nanotechnology unite the polymers'conductivity and the function of nanoparticles, which will greatly improve the processability of conducting polymers.Electrospnning has become a simple and inexpensive technique to produce sub-micron fibers and nanofibers, and the nanofibers fabricated in this way has the evenly distributed diameters. However it remains a great challenge to apply electrospinning to PANI as limited by its molecular weight and solubility. PANI blended with other polymers have been tried to form nanofibers using electrospinning technique [3-5]. Doping Fe₃O₄ in the PANI makes the composite nanofiber an integration of both conductivity and magnetism. In this paper, PANI and inorganic particles was homogeneously mixed by adding Fe₃O₄ nanoparticles into the ANi solution during its microemulsion polymerization. Polyaniline/Fe₃O₄ nanoparticle composite was prepared by microemulsion in-situ polymerizing aniline in the presence of Fe₃O₄ nanoparticles upon the use of ammonium persulfate (APS) as the initiator. hydrochloric acid(HCl) as intermingling acid, using cetyltrimethylammonium bromide (CTAB) as an emulsifying agent and normal butanol as an auxiliary emulsifying agent. With the help of the cation surface active agent CTAB, the Fe₃O₄ could be better coated by the PANI. The Fe₃O₄/PANI composite with regular structures, good stability, favorable solubility in organic solution, and high electric conductivity was obtained. The spinning solution was prepared by mixing Fe₃O₄/PANI with PAN. The existence of PAN greatly improved the spinnability of the PANI solution. The Fe₃O₄/PANI composite materials have great development potential in electrode materials, sensor, microwave absorption, etc.The article is mainly about use HRTEM, FT-IR, XRD, DSC, absorbing properties analytical techniques were used to characterize Polyaniline/ Fe₃O₄. The results indicated that a core-shell structure composite was prepared successfully. Further more, pure PANI solution was not able to be electrospun into the fibrous structure,so electrospinning of emeraldine base Fe₃O₄-polyaniline/ polyacrylonitrile(Fe₃O₄-PANI/PAN) blends with different composition ratios were performed using N,N-Dimethylformamide as solvent. Morphology and fibers diameters were investigated by scanning electronic microscopy (SEM), HRTEM and TGA.