Vol 48, No 5 (2017)

It was established experimentally that addition of the calculated amount of the cyclic oligomers isolated from extraction waters after treatment of equilibrium industrial granulate PA-6 to the initial reaction mixture during the hydrolytic polymerization of caprolactam leads to an increase in the degree of transformation of caprolactam into the sections of the linear chains. It was shown that the use of regenerated caprolactam, obtained by the technology used in OAO “KuibyshevAzot”, in the synthesis of PA-6 is a technologically safe and economically favorable method of using the cyclic oligomers formed during hydrolytic polymerization of caprolactam.

Analytic relationships for use in calculating the viscoelastic parameters from data of tests performed on a tearing machine with constant loading rate are given. A calculation of the viscoelastic parameters for carbon and quartz filaments using the Rzhanitsyn–Koltunov model is presented. The nature of the relaxation processes in filaments capable of forming fabrics from carbon and quartz filaments on a loom is demonstrated.

A suite of programs is developed to analyze photomicrographs of the structure of nonwoven materials. Such programs are needed for deciphering the structural distinctions in multidimensional characteristics of the studied objects that contain information about their states. This allows their use for classification of objects describable by characteristics of a different physical nature without their pre-standardization. The explicit form of the proposed measures is given and the effectiveness of their use in algorithms for automatic classification is shown for clustering of the images of polypropylene spunbond nonwoven material.

Mathematical models of processes that occur in the deflection of charged droplets of water-based lubricant in an electric field are considered.

The rheological characteristics (complex viscosity, equilibrium relaxation time, equilibrium shear modulus) of a viscoelastic spinning solution obtained in a viscometer and under actual fiber-spinning conditions are examined. It is shown that the optimal regimes for spinning stronger fibers could be predicted by using the spinning-solution rheological characteristics and correlation coefficients obtained in a viscometer.

We have established a connection between fracture and strengthening of fiber-reinforced composites and the fundamental concepts of time, space, and order. We have identified and considered in detail two types of processes in composites loaded by external forces. For processes of the first type, we have obtained formulas interrelating the initial and final degree of order/disorder, the relative scale, and the time of existence of the system. For processes of the second type, we have obtained a formula for estimating the instantaneous degree of order/disorder as a function of time, the initial and the equilibrium degree of order/disorder, and the relaxation time of the system. We have considered simultaneous occurrence of processes of the first and second type. Experiments on composites have confirmed the connection between the kinetics of processes of the first and second type and the fundamental concepts of time, space, and order.

The elasticity modulus of Rusar-NT aramid fiber was increased after electromagnetic treatment (EMT). A fiber sample was treated immediately after it was prepared and did not undergo additional chemical processing. The tensile strength increased by almost 20%; elasticity modulus, 11.48%. A comparison of IR and Raman spectra found that several spectral lines were shifted after EMT of the fiber.

The efficiency of ozone absorption by nonwoven polypropylene fibrous material prepared by industrial spunbond technology and changes of its chemical composition and structure after ozone treatment were studied. The effects of ozone treatment at low (250 μg/m³) and high (25 g/m³) ozone concentrations were compared. It was found that oxidative destruction in both instances was localized primarily on the fiber surface. The conditions under which the propylene nonwoven spunbond material was resistant to ozone were determined.

An innovative ecologically benign method for plasma sputtering of protective coatings onto textiles is proposed. The process for sputtering a powdered coating is simulated mathematically as a function of the distance from the nozzle to the point of powder introduction and the plasma temperature. Powdered composites that were most suitable for plasma sputtering of protective coatings onto light industrial materials were produced.

The main features related to the use of foam compositions during drying of fabrics are determined. The dynamic characteristics of a one-loop system for controlling the drying of textile fibers taking into account their properties are examined. Mathematical models of various textile fiber sample batches are presented.

Problems that arise in the development of modern energy-efficient technologies in the field of contact drying of fibrous materials are analyzed. A characterization of the basic structural drawbacks of existing systems used in the removal of condensate from drying cylinders is presented. A new channel method of steam heating of the drying cylinders of drum rollers is proposed and an analysis of its advantages as compared to standard methods is presented.