A method for predicting parameters of the structure of a reinforced composite based on epoxy-dian resin is described. The results of prediction of the structure parameters were validated by experimental data. The experimental data were processed using standard methods of the state system for ensuring the uniformity of measurements.
Expanding the application areas and operating conditions of marine ropes requires more thorough research into their deformation properties. Such research can be carried out using mathematical modeling of deformation processes, which include both viscoelastic relaxation and viscoelastic creep.
The heat-regulating properties of polyacrylonitrile films with added microcapsules containing paraffin were studied. The difference in the surface temperatures of films without paraffin and with added (5 wt
The possibility of using a native suspension of the microalga Chlorella vulgaris as a natural dye for coloring various fabrics was examined. Pretreatment methods of fabrics before dyeing were examined. Textile material samples dyed with the suspension were tested to assess dyeability and determine the color fastness to washing.
The hardness of composite materials obtained by impregnating nonwoven needle-punched fabrics made of polyethylene terephthalate and polyacetal fibers with an aqueous polyurethane dispersion was studied and depended on the formation of an intermediate layer during the fabric puncture process in which the packing density of fibers oriented parallel to the fabric surface exceeded the packing density of the fibers in the bulk. Polyurethane particles were concentrated predominantly in the intermediate layer. The maximum hardness of composite materials based on fabrics made of fibers of different chemical natures was observed for a degree of impregnation of 0.1. Increasing the degree of impregnation led to a decrease in the hardness of the composite materials that was associated with limited fiber mobility and the generation of localized stresses during indentation.
The abrasion resistance of composite materials obtained by varying the degree of impregnation of a nonwoven needle-punched fabric made from a mixture of polyethylene terephthalate fibers with linear densities of 0.22 and 0.66 tex with an aqueous polyurethane dispersion was investigated. Kinetic dependences of the mass reduction of the samples during abrasion on the degree of impregnation of the nonwoven fabric were obtained. A random change in the degree of wear was established. The mechanism of the behavior of the composite materials during abrasion depending on the degree of impregnation and the binder structure-formation process in the nonwoven fabric was described. A regression empirical model was developed to predict the mass reduction of the polishing material depending on the degree of impregnation and the duration of abrasive action.
The development of mathematical modeling methods for deformation processes of medical polymer yarns was a necessary step for further digital prediction and qualitative assessment of the performance of these materials.
A method for achieving insensitivity of an automatic tension regulation system to change in the moment of resistance by using a fuzzy regulator is described. To get the desired forms of transient tension characteristics, a linguistic description has been presented.
The effect of thermomechanical treatment modes on the mechanical properties of nonwoven needle-punched fabrics based on blends of bicomponent fibers with a linear density of 0.44 tex and polyethylene terephthalate fibers of 0.33 and 0.66 tex in a 30/70 ratio was studied. Materials produced by treating a fabric based on a blend of bicomponent and polyethylene terephthalate fibers of 0.33 tex showed a significant increase in the effective modulus reflecting tensile resistance at a roller temperature above 200°C and a treatment speed of <8 m/min. The effective modulus of materials obtained by treating a fabric based on a blend of bicomponent and polyethylene terephthalate fibers of linear density 0.66 tex monotonically increased with an increase in the roller temperature and a decrease in the treatment speed.
The effect of pressure in a hydraulic tension system of guiding rollers on the porosity coefficient and mechanical properties of materials produced by thermomechanical treatment of nonwoven needle-punched fabrics based on polyethylene terephthalate and bicomponent fibers in ratios of 90/10 and 70/30 wt
A method for improving the mud- and water-repellent properties of materials with chemical fibers to produce activewear and special clothing is discussed. Plasma modification of textile materials using a nonequilibrium, low-temperature, low-pressure plasma activates the fiber surface, producing a protective coating with better water- and mud-repellent properties than control samples.
The development of numerical methods for predicting deformation-recovery processes in aramid textile yarns allows the properties of these materials to be comparatively analyzed, the relationship between mechanical properties and structure to be studied, targeted technological control of properties during the development and production of new materials to be conducted, and short-term and long-term mechanical impacts to be predicted.
The present article uses the Boltzmann-Volterra integral relations to study digital prediction of deformation processes in marine polymer ropes. The separation of the total deformation and mechanical work of deformation of marine polymer ropes into components is also considered.
Currently, the industrial focus is on developing new materials, saving energy and resources, and making sure production and products are as eco-friendly as possible. In the practice of construction and road works, increasing attention is being paid to geotextile nonwoven materials, the use of which improves the quality of roads and road structures, as well as increases their effective service life. The technology for producing nonwoven materials uses all kinds of textile raw materials, including lowgrade, short-staple, and non-spinnable fibers, as well as fibers regenerated from scraps and rags.
Experiments have shown that when the clamping length of yarn is reduced from 500 mm, as specified by the standard, to less than 10 mm, its breaking elongation sharply increases. The possibility of predicting the breaking elongation of yarn at a clamping length numerically equal to the height of the stitch row in warp knitted fabric is considered. Summing this characteristic with the maximum elongation of the stitch structure obtained on the basis of Dalidovich model allows the breaking elongation of knitted fabric to be calculated with sufficient accuracy. It is advisable to apply this method when designing technical fabrics that are subject to high loads.
The present paper studies the digital prediction of elastic, viscoelastic, and plastic deformation of nonwoven geotextiles. Problems of determining these deformation components are solved through computational prediction using the parameters of a nonlinear viscoelastic creep model.
The article discusses the development of flexible thermal protection system for aircraft made from high temperature materials produced in Russia. The obvious advantages of flexible thermal protection should be exploited by developers of domestic reusable and hypersonic aircraft. Domestic quartz textile materials have a combination of mechanical and thermophysical properties that exceed the similar properties of foreign quartz textile materials.
The use of highly stretchable textile materials incorporating elastomeric threads is rapidly developing. Therefore, the application of such materials in areas related to the production of compression medical devices arouses a legitimate interest.
The present article examines spectral modeling of creep in nonwoven geotextiles used in road construction. The shape of the creep delay spectrum is shown to be graphically determined by the value of a single parameter, i.e., the creep intensity.
Silica glass-fiber materials are manufactured by acid treatment of glass-fiber materials of a special composition. Such treatment selectively removes basic components, leading to an increase in the mass fraction of high-temperature resistant oxides (SiO2 and Al2O3) to almost 100
