芳纶纤维/浆粕表面能及其复合纸性能

测定了几种间位芳纶短纤维、芳纶纯浆粕及其复合纸的表面接触角，结合倒数平均调和方程计算了芳纶纤维及复合纸的表面能。通过芳纶纸中纤维与浆粕界面张力及粘附功的计算，分析芳纶纤维及浆粕的表面能与其复合纸性能的关系。结果表明:采用水和乙二醇作为接触角测试液体时，芳纶纤维及浆粕的表面能为35～45 mJ·m-2。其中，芳纶短纤维表面能稍高于芳纶浆粕，芳纶短纤维及浆粕的极性分量大于色散分量，表面能越高越利于增强表面可润湿性，粘附功越大。热压导致芳纶复合纸表面能下降，相对于Nomex纸，自制芳纶复合纸的表面能降低得更明显。芳纶短纤维与浆粕的色散分量和极性分量越匹配，表面能之差及界面张力越小，则芳纶复合纸中纤维之间的粘接力越强，抗张指数也越高。 

Surface energy of aramid fiber/pulp and their sheets properties

The surface contact angles of several meta-aramid fibers and meta-aramid pulps as well as their sheets were measured，and the surface energy of aramid fiber，aramid pulp and sheet was determined according to the harmonic mean-based Wu equation. The relationship between the surface energy and sheet properties in sheet processing was discussed according to the surface energy as well as the interfacial tension and work of adhesion of aramid fibers and pulps. The results show that the surface energy of aramid fibers and pulps is in the range of 35～45 mJ·m-2，the surface energy of fibers is slightly higher than that of pulps，the polar component of surface energy is larger than the dispersion one，and the wettability and work of adhesion are enhanced with increase of the surface energy of aramid fibers and pulps，when water and glycol are employed as the testing liquids. The surface energy of aramid sheet decreases during hot-press process，and compared to Nomex sheet，the surface energy of self-made aramid sheet decreases sharply after hot-press process. The better the matching of polar component with dispersion component，the smaller the difference of surface energy and the smaller the interfacial tension，the stronger the adhesion between fibers and pulp with the improved strength of aramid sheet.