Synthesis, Properties, and Processing of Melt-Spinnable Acrylonitrile Copolymers

Carbon fiber (CF) which is one of outstanding structural materials have received much attention for application such as composite materials, textiles, microelectrodes, and catalyst because of its superior mechanical properties, heat resistance, low thermal expansion, chemical resistance, and so on. CF has been developed from several kind of precursors such as polyacrylonitrile (PAN), pitch, and rayon. In particular, because CF derived from PAN shows especially high mechanical properties and its manufacturing process has been well studied, CF commercial makers has mainly used PAN as a CF precursor. Until now, CF and its composites have been only applied in high tech fields such as aerospace because of the cost problem. Recently, those application to automobile is a rising issue because those properties, light weight and high strength, can make increase of performance and fuel-efficiency. However, reducing the cost of CF is a precondition for these application. In addition, because the automobile application is not required for very high mechanical properties, a little decrease of the properties is allowed. In this regards, many research institutes have found the method for reducing manufacturing cost. There have been several approaches such as using low cost precursors and changing manufacturing procedure. In particular, traditional PAN precursors is prepared by the wet spinning which required expensive organic solvent recovery process and waste water treatment process. In this research, we have synthesized acrylonitrile copolymers containing functional components for reducing manufacturing cost by using melt spinning process which can spin fibers with a high speed than wet spinning and do not require solvent and water handling. In conclusion, we could prepare acrylonitrile fibers by melt spinning and stabilize the fibers by using other treatment with thermal method. In the presentation, the thermal and rheological properties of the synthesized polymers will be mainly discussed in detail.