燃料电池用PAN/Lyocell复合碳纤维纸的制备与性能研究

Preparation and Properties of PAN/Lyocell Composite Carbon Fiber Paper for Fuel Cell

本研究以Lyocell纤维为增强纤维、PAN短切碳纤维为主体纤维,制备燃料电池气体扩散层用复合碳纤维纸(简称碳纤维纸),探究了磨浆强度对Lyocell纤维浆料和纤维特性的影响,分析了Lyocell纤维的添加对碳纤维的分散性与碳纤维纸的强度性能、透气性能、导电性能的影响。结果表明,Lyocell纤维的添加有效提升了碳纤维的分散性能,提高了碳纤维纸前驱体(CPP)的匀度指数和强度性能,改善了碳纤维纸的强度性能、透气度和导电性能,当碳纤维与Lyocell纤维质量比为7∶3时,碳纤维纸的性能最佳,拉伸强度为14.3 MPa,抗弯强度为5.9 MPa,透气度为248 mm/s,平面电阻率为5.48 mΩ·cm。

In this study,Lyocell fiber(as reinforcing fiber)and chopped PAN carbon fiber(as main fiber)were used to prepare composite carbon fiber paper(referred to as carbon fiber paper)for fuel cell gas diffusion layer.The influences of refining strength on the pulp and fiber properties of Lyocell fiber were investigated,and the effects of Lyocell fiber addition on the dispersion of carbon fiber,and strength,permeability and conductivity of carbon fiber paper were clarified.The results showed that the addition of Lyocell fiber effectively improved the dispersion performance of carbon fiber,the uniformity index and the strength performance of carbon fiber paper precursor(CPP)and carbon fiber paper,and air permeability and electrical conductivity of carbon fiber paper.When the mass ratio of carbon fiber to Lyocell fiber was 7∶3,the carbon fiber paper had the best performances,with tensile strength of 14.3 MPa,bending strength of 5.9 MPa,air permeability of 248 mm/s,and planar resistivity of 5.48 mΩ·cm.