间位与对位芳纶沉析纤维及其纸基绝缘材料的结构特性对比研究

Structures and Properties Comparison of Meta-aramid and Para-aramid Fibrid and Their Paper-based Insulation Materials

通过光学显微镜(LM)、扫描电子显微镜(SEM)、纤维形态分析仪(Morfi Compact)、X射线衍射仪(XRD)、热重分析仪(TGA)及纸张性能检测等手段分别研究了间位芳纶沉析纤维和对位芳纶沉析纤维的表观形貌、形态参数、结晶特性、热学性能,并对比分析了其纸基绝缘材料的主要性能。结果表明:间位芳纶沉析纤维呈现无规则带状结构,形态柔软,尺寸较大,易于缠绕;对位芳纶沉析纤维呈现薄膜皱褶状结构,在水介质中均匀分散并自由舒展,纤维均一性较好,细碎化程度较高。两种纤维均具有明显的无定形结构和优异的热性能,其中对位芳纶沉析纤维的结晶度较高,热稳定性较好。两种纤维配抄成纸的介电性能接近,但对位芳纶沉析纤维配抄成纸的机械强度和热性能更具优势,匀度较好且吸湿性较弱,是一种在耐高温纸基绝缘材料领域更具应用优势的新型纤维。

The microstructure, morphological parameters, crystalline characteristics, and thermal properties of meta-aramid and para-aramid fibrid were investigated via LM, SEM, Morfi Compact, XRD, TGA, and other paper performance test equipment, and the main properties of their paper-based insulation materials were analyzed. The results show that the meta-aramid flbrid appears irregular banded structure, flexible shape, and bigger size, and it is easy to twine; the para-aramid flbird exhibits thin film structure with wrinkled surface and has uniform size and high degree of fibrosis, and it can well disperse and stretch in water. The two aramid fibrids have obvious amorphous structure and excellent thermal stability. However, the para-aramid fibird has higher crystallinity and thermal stability. The aramid papers made of the two fibrids have similar dielectric properties, but the paper made of para-aramid has more advantages in mechanical strength and thermal stability, the evenness is better, and the hygroscopicity is weaker, which indicates that the para-aramid flbrids can be widely used in high temperature resistant paper-based insulation materials.