向炭纸初坯中引入长炭纤维网,以改性酚醛树脂为黏合剂对炭纸坯体进行浸渍,经模压固化、炭化和石墨化工艺制得质子交换膜燃料电池(PEMFC)用炭纸。研究长炭纤维的添加对炭纸性能的影响。研究结果表明:在兼顾炭纸具有优良透气性的前提下,长纤维的加入对炭纸起到了既增强又增韧的效果,并且提高了炭纸的导电能力;当添加的长炭纤维占炭纸初坯的10%(质量分数)时,炭纸的综合性能最好,其性能参数如下:厚度为0.23 mm,密度为0.47 g/cm3,电阻率为2.39 m-.cm,抗拉强度、抗弯强度及弯曲挠度分别为28.15 MPa,83.89 MPa和1.1 mm,孔隙率为75.8%,透气率为4 906.75 m3/(h.kPa.m),满足燃料电池气体扩散层用炭纸的需要。
The initial carbon fiber preforms were added with long carbon fiber nets,and impregnated with modified phenolic resin which acted as the binder.The green samples were then treated by molding,carbonization and graphitization processes and the carbon paper for PEMFC was obtained.Influence on the carbon paper made by the introduction of the long carbon fiber nets was studied.The results show that in the premise of meeting the need of the gas permeability of carbon paper,the introduction of the long carbon fiber net plays a role of not only toughening but also strengthening the carbon paper and increasing its conductivity.The carbon paper can reach the optimal performance with the long carbon fiber net 10% content and on the whole meets the need of PEMFC.The properties are as follows: the thickness is 0.23 mm,the density is 0.47 g/cm3,the resistivity is 2.39 mΩ?cm,the tensile strength,bending strength and bending deflection are respectively 28.15 MPa,83.89 MPa and 1.1 mm,the porosity is 75.8%,the gas permeability is 4 906.75 m3/(h?kPa?m2).