Altering Moisture Transport Mechanisms in Multilayer Material Systems via Open Channel Networks for Enhanced Comfort

This study examines how the composition and structural configuration of two- and three-layer polymer-based systems influence thermophysiological comfort by altering water vapor transport mechanisms. Open moisture-transport channel networks were introduced into the top layer via controlled perforation to modify the dominant vapor transmission pathways. The results reveal nonadditive sorption behavior in multilayer systems, in which low-permeability outer layers constrain overall moisture transport. The incorporation of engineered open channels mitigates this limitation by enabling an additional Fickian diffusion pathway, thereby enhancing water vapor permeability and moisture uptake. The effect is particularly pronounced in systems containing a synthetic leather layer. Increasing the moisture transport channel coefficient to 0.0145 enhanced the water vapor permeability of synthetic leather by up to 3.5 times and of natural leather by up to 1.5 times. Consequently, the water vapor absorption of the corresponding multilayer systems increased by 14-73 times (from 0.03-0.60 to 2.26-8.33 mg cm^-2) for synthetic leather systems and by 45-61% (from 12.8-20.1 to 18.6-32.3 mg cm^-2) for natural leather systems. This work establishes a relationship between layer-specific properties and system-level moisture transport, demonstrating that targeted modification of vapor transfer pathways can effectively enhance thermophysiological comfort and moisture management in multilayer material systems, particularly in clothing and accessory applications.