The study of the structure and structure of non-woven fabrics of various manufacturers is presented. The results of analysis and mathematical modeling of the process of spontaneous liquid absorption by a porous fibrous medium are given, which make it possible to determine the height of liquid rise depending on the porosity of the material and the absorption time, calculate the permeability index of the nonwoven fabric taking into account physical parameters of the liquid and geometric characteristics of the material. Criterion equations are proposed for evaluation of properties and prediction of mechanical characteristics of nonwoven materials. The monograph is intended for engineers, graduate students and researchers specializing in the development of new materials, as well as textile materials science.