Interlayer Liquid Transport in Multilayer Cellulose-Based Nonwovens

Interlayer liquid transport in nonwovens is crucial for a wide range of applications, including e-cigarette atomizer cores, wound dressings, and baby diapers. However, existing research was largely confined to single-layer nonwovens. Here, we systematically elucidated the liquid transport behaviors in single-layer and multilayer nonwovens composed of cellulose fibers. For single-layer nonwovens, liquid diffusion was primarily governed by fiber hygroscopicity and interfiber pores. For multilayer nonwovens, layer division interrupted the transport pathways and increased penetration time, whereas reducing nonwoven thickness or increasing assembly density shortened the penetration time. Based on the orthogonal experiments, fiber arrangement across multiple layers of the nonwovens was found to significantly affect the overall penetration time. Pioneering models were established to study the correlations between the interlayer penetration time with both the assembly density and fiber arrangement through regression analyses. By integration of these models, an application-oriented computational tool was developed to transform these theoretical insights into an accessible engineering resource, aiming to provide guidance for the design and optimization of liquid transport in e-cigarette atomizer cores.