Kucherenko Y. Development of technology for obtaining the highly elastic fibrous materials from secondary raw materials

The urgency of the work is due to the need to expand the range of non-woven materials from a mixture of chemical fibers based on industrial fibrous waste for various purposes, in particular to obtain highly elastic materials for thermal insulation of complex geometric shapes. In the dissertation work the important scientific and applied problem of obtaining nonwoven materials with adjustable properties from a mixture of chemical fibers on the basis of industrial fibrous waste is solved. The practical significance of the received results is that for the first time a method of processing chemical fiber waste to obtain of the highly elastic nonwovens has been proposed. The use of natural fibers of flax, hemp, bamboo, cotton as an additional component in the composition of nonwoven materials based on PU/PA-6,6 fibers allows to obtain the insulating materials for the automotive, construction, textile and footwear industries. A methodological approach to the construction of two-dimensional vector models of nonwoven composite materials with a controlled nature of the distribution of individual structural elements has been developed. The structural features of nonwoven materials based on fibrous waste of complex threads PU/PA-6,6 at different ratios of components are determined. The scheme of process is developed and norms of a technological mode of manufacturing of thermobonded nonwoven materials on the basis of fibrous waste (PU/PA-6,6) are defined. It is proved that the addition of PET fibers to the initial mixture allows to increase the relative strength of nonwoven materials (12-15 times) in comparison with the original sample (PU/PA-6,6). A method for determining the textural characteristics of needle-punched and heatbonded nonwovens using various algorithms based on the method of image analysis. A linear correlation between textural parameters and fractal dimension for nonwoven fibrous materials based on (PU/PA-6,6) with different amounts of adhesive fibers has been established. It is established that the use of up to 50 wt.% natural flax and hemp fibers allows to obtain nonwoven material with a sufficiently low thermal conductivity and lower surface density, which together with low hygroscopicity and sufficient strength provides the possibility of using these materials for thermal insulation of complex geometric shapes.