Abstract
Because of poor surface hydrophilicity, meta-aramid fibers readily form flocs by intertwining or interlacing, and this severely affects the uniformity of meta-aramid paper. To investigate the flocculation mechanism of meta-aramid fiber suspensions, the critical flocculant concentration, shear, and compressive network strength of meta-aramid fiber suspensions were examined. A hand sheet former was used to study the influence of the yielding properties of suspensions on the uniformity of meta-aramid paper, and the relationship between the formation index and rheological properties was determined. The results showed that the critical gel concentration ranged from 0.37 to 0.68 g/L, which was much lower than that of plant fiber suspensions. In addition, the compressive yield stress ( P y ) and shear yield stress ( τ y ) of the meta-aramid fiber suspensions were found to increase linearly and exponentially, respectively, with an increasing concentration, and the uniformity index of the paper sheets was found to depend on a power of τ y ⋅ P y . This provides an effective method for predicting paper sheet uniformity.
Highlights
Because of their excellent chemical and thermal stabilities, heat resistance, and mechanical strength, meta-aramidpaper-based materials have recently received considerable attention in high-end fields such as defense, power, and transportation
Aramid fibers are prone to flocculation because of their long length and poor surface hydrophilicity, and this severely affects the uniformity of aramid paper and limits the application of aramid-paper-based materials in relevant high-end fields
It can be observed that the short fibers are straight and have a smooth surface, whereas the fibrids are curled and have a rougher surface, which is favorable for the intersecting strength of aramid paper
Summary
Because of their excellent chemical and thermal stabilities, heat resistance, and mechanical strength, meta-aramidpaper-based materials have recently received considerable attention in high-end fields such as defense, power, and transportation Their unique physical and structural features give them beneficial tensile, electrical, and chemical properties, which have attracted significant attention in academia in several disciplines [1,2,3]. The structural strength of the fiber network can be characterized based on two types of stresses: compressive and shear yield stress. The objective of this study was to investigate the critical flocculant concentration, shear, and compressive yield stress of suspensions of the mixture of meta-aramid short fibers and fibrids, based on the rheological theory. The results obtained may be used to increase the efficiency of the manufacturing process
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.