高模量碳纤维的现状及发展(2)

主要介绍了国内外聚丙烯腈基和沥青基高模量碳纤维的研究现状及发展趋势。⑴高模量碳纤维的发展方向:1980年代,两大高模量碳纤维都朝着高强高模方向发展,以满足飞机主承力结构件高强高模并重的需要,因而促使高模量碳纤维的性能从单一高模化向高强高模化方向迈进,如东丽公司的M50J和M60J的抗拉伸强度(σ)分别为4.12 GPa和3.92 GPa,抗拉伸模量(E)分别为475 GPa和588 GPa,与M50(σ:2.45 GPa,E:490 GPa)相比均大幅度提高;1990年代率先研制出XN-70(σ:3.3 GPa,E:690 GPa)和FT-700(σ:3.3 GPa,E:700 GPa)沥青基高强高模碳纤维产品不久,美国AMOCO公司也生产出Thorne K-1000(σ:3.1 GPa,E:956 GPa)商品,满足了工业界的需求。⑵原丝的品质是提升高强高模碳纤维性能的关键:人们特别关注聚合物单体、溶剂、环境等的净化,以及聚合纺丝工艺参数的选择和调整,目的是如何能生产出低灰份杂质,细直径,高碳收率,高取向度和结晶度,毛丝少,柔韧性好,均匀稳定的优质原纤维。优质原纤维是制备高强高模的物质基础。⑶热处理制备工序、设备选型及工艺参数的调控也是提高高强高模碳纤维性能不可或缺的条件:人们在热处理过程用DSC-TG(热分析仪)、EA(元素分析仪)、FE-SEM(场发射扫描电镜)、HRTEM(高分辨透射电镜)、XES(X-射线能谱仪)、XRD(X-射线衍射仪)、Raman(拉曼光谱)、NMR(核磁共振仪)、STM(原子力显微镜)和AAS(原子吸收光谱)等先进的测试分析方法以及万能材料试验机等,研究各工序的工艺参数对产品性能和结构的影响,并详细的用图表阐述之。前人研究的成果加速了世界高强高模碳纤维性能的提升。进而提出了提高我国高强高模碳纤维的关键技术(例如研制非硅系新油剂,加强各工序的净化度和设备加工精度,强化工艺参数调控精度和加强灵活可变性,分析测试的准确度和测试方法的统一性等)。同时简介了高模量碳纤维的应用领域和前景。

The Current Status and Development Trend of High Modulus Carbon Fibers (2)

The research current status and development trend of PAN and pitch based high modulus carbon fiber in home and abroad were introduced mainly.⑴ Development trend of high modulus carbon fiber.In 1980s,both PAN based and pitch based high modulus carbon fiber were developed with high tensile strength as well as high modulus to meet the need of high tensile strength-high modulus carbon fiber for primary structural materials of aircraft,so the development trend of high modulus carbon fiber was changed from only high modulus to high modulus with high strength.In very short years,series MJ products of carbon fiber were produced by Toray Company of Japan and available in the market.M50J and M60J are representatives,and their tensile strength（σ） are 4.12 GPa and 3.92 GPa,respectively,and modulus（E） 475 GPa and 588 GPa,which are improved greatly compared with that of carbon fiber M50（σ,2.45 GPa;E,490 GPa）.In 1990s,pitch based high modulus carbon fiber with high strength,XN-70（σ,3.3 GPa;E,690 GPa） and FT-700（σ,3.3 GPa;E,700 GPa） were firstly developed in Japan,and soon later Thornel K-1000（σ,3.1 GPa;E,956 GPa） was produced in USA,reaching the requirement of industries.⑵Quality of precursor is the key factor of improving the properties of high modulus carbon fiber.The purification of polymer unit,solvent and spinning atmosphere,as well as the parameters of polymerization,spinning process are specially focused,because excellent precursor fiber with low ash content,small diameter,high carbon yield,high preference orientation and crystalline degree,low decollation,stability and uniformity is the foundation of preparing high strength high modulus carbon fiber.⑶ Procedure of heat treatment,equipment option and technology parameters control also plays an important role in improving the properties of high strength high modulus carbon fiber.DSC,TG,EA,FE-SEM,HRTEM,XES,XRD,Raman,NMR,STM and AAS,along with INSTRON tester are used to study the effects of every procedure parameter on the structure and properties of the products,which are illustrated in detail by charts and diagrams,aiming to improve remarkably the properties of high strength high modulus carbon fiber on the basis of the previous work.In the meantime the key technologies for improving China’s high strength high modulus carbon fibers are proposed,such as synthesis of new non-silicone oil agent,air purification of every procedure,precision of equipment,accuracy adjustment of process parameters,standardization of analysis and measurement methods,etc.At the end of this paper,application field and prospect of high modulus carbon fibers are recommended briefly.