超高分子量聚丙烯腈在碳纤维原丝上的应用及拉伸行为研究进展

超高分子量聚丙烯腈(UHMWPAN)由于结晶度高、分子链结构规整、端基少,成纤后的缺陷也少,因此在制备高强度聚丙烯腈原丝以及高强度碳纤维方面有着重要的应用。文中介绍了用高相对分子质量(340万占3%,34万占97%的)的聚丙烯腈树脂进行溶液纺丝并制备碳纤维原丝以及碳纤维的工艺,并重点介绍了超高分子量聚丙烯腈凝胶膜的拉伸性能、超高分子量聚丙烯腈溶液的流变性能等。流变学研究表明,随着PAN相对分子质量的增大,纺丝液的黏度也会剧增,造成溶液的纺丝过程变得愈加困难。提高UHMWPAN纺丝液的温度,能有效减低溶液纺丝时的阻力。因此,开发UHMWPAN高温纺丝技术可能是未来高强度碳纤维原丝的发展方向。

Progress of Ultra High Molecular Weight Polyacrylonitrile on the High Strength Carbon Fiber Precursor and Its Tensile Behavior

Due to its high crystallinity,neat structure,less molecular chain end groups,less defect,ultra high molecular weight polyacrylonitrile has outstanding tensile properties,especially suitable for the preparation of high strength polyacrylonitrile precursor and high strength carbon fiber.In this paper,the preparation of precursor prepared by solution spinning of ultra high molecular weight polyacrylonitrile and the corresponding carbon fiber were introduced.Moreover,the tensile properties of ultra high molecular weight polyacrylonitrile gel film,and the rheology of the solution of ultra high molecular weight polyacrylonitrile were also introduced.With increase of the molecular weight of PAN,the viscosity of the spinning solution will increase sharply,and the spinning process of the solution becomes more and more difficult.The rheological study shows that with increase of the temperature of UHMWPAN solution,resistance of solution spinning could be effectively reduced.Therefore,the development of high temperature spinning technology of UHMWPAN solution may be the future development direction of the high strength carbon fiber precursors.