Water-resistant and vapor-permeable textile laminates containing nanofiber membrane as footwear lining

This paper aims to test the suitability of two nanofibrous membranes as a lining in outdoor shoes, especially leather ones. The motivation is that leather shoes offer some water resistance but are not fully waterproof. By inserting a membrane, higher hydrostatic resistance is achieved while maintaining the vapor permeability of the upper material - leather. Two nanofibrous membranes were developed, and three-layer and four-layer laminates were made from them. In addition to the membrane, the lining, and the top material, the four-layer laminate also contains a thermal insulation layer. These laminates were investigated concerning the following properties: hydrostatic resistance, water vapor permeability, thermal insulation, and air permeability, while the first two properties were chosen as crucial. For the study to be complete, the sample set was supplemented with commercially available membranes. It was found that laminates containing nanofiber membranes provide interesting properties: hydrostatic resistance higher than 10 m and water vapor permeability around 5 Pa.m2.W−1, which is promising, especially considering the vapor permeability of the shoe’s upper material – leather. From the selected laminate, a cut was designed, and an inner shoe was realized, which was subsequently incorporated into outdoor leather footwear.