热压温度对芳纶1414纤维/1313浆粕复合纸微区结合特征的影响
Effect of hot pressing temperature on inter-binding feature between para-aramid fiber and meta-aramid fibrids in composite paper

针对国产间位芳纶纸力学性能不足的问题，采用芳纶1414（聚对苯二甲酰对苯二胺）短切纤维与芳纶1313（聚间苯二甲酰间苯二胺）浆粕复合，制备芳纶1414纤维/1313浆粕复合纸，研究不同温度下芳纶1414纤维/1313浆粕复合原纸的热压性能，分析纸张的强度性能；采用SEM、压汞仪和FTIR研究芳纶1414纤维/1313浆粕复合纸的内部结构变化。阐述热压温度对芳纶1414纤维/1313浆粕复合纸热压过程中短切纤维与浆粕之间的相互作用以及微区结合特征的影响。结果表明：芳纶1414纤维/1313浆粕复合纸在热压温度为280℃、热压时间为6 min、热压压力为15 MPa条件下，短切纤维与浆粕之间黏结状态良好，自制芳纶1414纤维/1313浆粕复合纸孔隙率为23.21%，其抗张指数最大值为212.2 N·m·g-1，为Nomex T410纸强度的两倍。FTIR结果表明，随着热压温度的升高，纸张中未形成新的化学键，芳纶分子间氢键缔合程度明显增大，是芳纶1414纤维/1313浆粕复合纸强度提高的主要原因。 Many efforts had been made aiming at the issue of lower mechanical performance of domestic aramid paper composites, which made of meta-aramid fibers and fibrids. In the present work, the aramid paper composites were prepared with para-aramid (1414) chopped fibers and meta-aramid (1313) fibrids, abbreviated as 1414/1313 paper. The hot-pressing characteristics and strength properties of the aramid sheets under various temperatures were investigated. The variations of internal structure in aramid paper composites were characterized by using SEM and FTIR. The effects of hot-pressing temperature on interactions and inter-binding features between the fibers and fibrids were studied. The results show that a favorable bond feature between the chopped fibers and fibrids is formed when the papers were hot pressed at 280℃, 15 MPa for 6 min. A maximum tensile index of 212.2 N·m·g-1 with paper porosity of 23.21% occurs, which may about twice that of the commercial T410 Nomex paper. In addition, the FTIR spectrum results verify that no new chemical bonds are formed with the increase of hot pressing temperature, but the significant strength increase of intermolecular hydrogen bond association, which is the main cause of paper mechanical properties improvement. 陕西省科技统筹创新工程计划（2015KTCQ01-44）