Formation of Baked Yarn of Complex Structure, Methods for Determining The Hairiness of The Yarn and Hair Characteristics

This paper examines the differences between the main purpose of the process of falling from individual fibers in a given linear density, density and elasticity and the methods of determining the hairiness of the yarn, the hairiness of the yarn is determined by the number of knots per unit length.

РОЗРИВАЛЬНІ ХАРАКТЕРИСТИКИ КОМПЛЕКСНОЇ ПОЛІЕТИЛЕНОВОЇ НИТКИ

Purpose. To investigate the influence of the number of threads resisting to break, the griping length, and the change in the position of the interlacing point when threading with a loop the breaking characteristics of complex polyethylene threads in the form of a loop.Methodology. In the course of the research, experimental research methods were used to determine the breaking characteristics of high molecular weight polyethylene threads on a WDW-5ES tensile machine in accordance with DSTU ISO 2062: 2004, the main provisions of textile materials science and knitting theory, methods of analysis and synthesis of the results obtained. Results. Based on the results of the studies, the influence of different factors on the breaking characteristics of complex multifilament threads was determined, namely: the influence of the number of threads resting on the break, the griping length and the change in the position of the weave point when threading with a loop. In the course of research, the griping length was changed in the range from 25mm to 300mm, and with a stable griping length (100 mm), the location of the thread weave point relative to the lower grip (25mm, 50mm, 75mm) was changed. It has been found that the breaking characteristics of a complex polyethylene yarn are influenced by both the griping length and the location of the weave point in the case of a loop-shaped break. The magnitude of the specific breaking force in the study of loop-shaped rupture is greater than in the study of straight segments of the thread. This is due to parallelization and compaction of the filaments due to the presence of the weave point on the thread that resists tearing. Scientific novelty. Regularities of the effect of griping length, linear density, and location of the point of weave of the complex high molecular threads in relation to the downer and upper grip are established provided that the griping length (100 mm) remains unchanged on the value of breaking load and elongation.Practical significance. Determination of the factors affecting the breaking characteristics of a complex polyethylene yarn will allow in the future, at the stage of designing the structure of knitwear in computer 3D modeling systems, to provide for the magnitude of the breaking force.

Comparative modelling of the destruction of a soft armour barrier using two- and threedimensional textile materials based on orthogonal fabrics

The article suggests an approach to virtual testing of textile materials for high-speed penetration. The comparison of two materials developed using different technologies – 3D orthogonal fabric and a package of plain weave fabric is carried out. For this purpose, such parameters of fabrics are selected so that the surface density is identical, the number of layers is the same, the linear density of the threads would be the same. The material of the threads is aramid fibre. In general, according to the assessment along the warp and weft, the lesion area for 3D orthogonal tissue is higher by up to 30 %. At the same time, 31.7 % more kinetic energy of the bullet was extinguished.

Influence of the hydrodynamic degumming process on the quality of decorticated flax fibers

The study explored the impact of the hydrodynamic degumming process applied for decorticated monomorphic flax on fiber quality. The experiment was designed as the first stage of research leading to the development of a method for decorticated flax fiber elementarization and cottonization; in particular, effectively dividing the fiber bundles to ensure low linear density and reducing impurities in the content, to make the fibers suitable for cotton spinning systems. The degumming process of the decorticated fibers covered hydrodynamic disposal of the gluing substances, mainly pectins from the fibers, with use of a specially designed lab-scale Model Device for Physical Degumming of the Flax Fibers. The degummed fibers were tested for linear density, length, impurity content and chemical composition by thermogravimetric analysis combined with the analysis of evolved gases (Fourier transform infrared spectroscopy) and analysis of images of fiber cross-sections and longitudinal views from a scanning electron microscope. The study outcomes allowed us to determine the optimal parameters of the degumming process applied for decorticated flax fibers, in which the obtained fibers were of the highest quality. It was found that the optimal parameters of the process were a bath temperature of 30°C and a degumming process duration of 24 hours. These lab-scale process conditions were used in further work on the degumming process of flax fiber carried out on a semi-technical scale, followed by a mechanical cottonization of the fiber, at the final stage of the technological chain.

The structure of productivity elements of durum wheat varieties of Saratov selection

The objects of the study were plants of 14 varieties of durum wheat Triticum durum Desf., permitted for use at different times in the period from 1975 to 2014. An analysis of the elements of ear productivity in durum wheat plants of Saratov varieties under the conditions of 2020 was carried out. The varietal features of the development of the spike of the main shoot were revealed according to a number of characteristics: the number of spikelets in a spike, the number of grains in an ear, the weight of a grain, the number of ungrained and grained spikelets. The height of the plant and the length of the spike were measured. On the basis of the data obtained, the selection indices were calculated – the Canadian index, the Mexican index, the index of the linear density of the ear, the morphogenetic index of productivity. A cultivar with a balanced type of morphogenetic systems was revealed in terms of the elements of ear productivity – the number of spikelets, the number of caryopses and their weight – Luch 25. This cultivar is characterized by the most developed embryonic shoot among the studied cultivars, as well as the maximum length of the embryonic root system and a high growth rate root system of the seedling.

Nondestructive Test Technology Research for Yarn Linear Density Unevenness

Yarn linear density and linear density unevenness between fragments involve the mass and mass variation of yarn per unit length, which are important indices to reflect the uniformity of yarn thickness. Aiming at the shortcomings of the traditional testing method, which uses a yarn length tester to test these indices by counting length first and then cutting and measuring weight, a testing device that measures weight and counts length synchronously is designed and developed, so that the yarn can be continuous, recyclable, and reusable. Length counting is conducted by a length-counting disk connected to a photoelectric coded disk, and the result of length counting can be accurate to 0.01 m. The original skein frame with a perimeter of 1 m is replaced, so that the error caused by yarn overlapping is avoided. Through program control, the testing of a plurality of groups of linear density values can be completed at one time to calculate the linear density unevenness of different fragments of yarn, and the yarn can be led to a recovery spool through a yarn guide cylinder to form a new package. Polyester/viscose 65/35 blended yarn was taken as a test sample and subjected to statistical analysis using SPSS software. It is found that the results of the newly developed device are closer to the arbitration value; the whole experiment is completed at one time, which avoids the secondary error and reduces the labor intensity; and the raw materials can be recycled, which saves labor and raw material costs. The device has high value for industrialization and popularization.

Thermo physiological comfort of single jersey knitted fabric derivatives

The main aim of this study is to determine the thermo-physiological comfort properties of single knit fabrics and their derivatives. As the Single Jersey knitted fabrics are the most widely used fabrics in the apparel sector, they have been selected for the analysis purpose. Derivatives of single jersey are developed and compared in order to understand the influence of structural variations. Physical properties e.g. thickness and areal density were evaluated for all knitted fabrics with 100% cotton yarn having three different yarn linear densities and after different stages of relaxation. Various thermo-physiological properties have been studied by changing the combed cotton yarn linear density as well as the structure of single knit fabric. Air permeability, thermal insulation and relative water vapor permeability of the fabrics were observed and investigated under wet relaxed states. It is determined that fabric physical properties are affected by changing yarn linear density and by the dry or wet relaxation stages. The percentage/number of tuck stitches (NTS), location of tuck stitches (LTS) and ratio of tuck to knit stitches (RTKS) have strong influence on physical and thermo-physiological properties of single knit fabrics, even though other knitting parameters remained the same.

Tribology of The Sock-Skin Interface – The Influence of Different Fabric Parameters On Sock Friction

The purpose of this parametric design of experiments was to identify and summarize how the influence of knit structure (single jersey vs. terry), fiber composition (polyester vs. cotton), fiber linear density (30/1 Ne vs. 18/1 Ne & 1/150/34 vs. 2/150/34), and yarn type (filament vs. spun) affected the frictional profile across the sock-skin interface, and then relate these factors to friction blister incidence. Friction testing trials were completed against both a polypropylene probe and a synthetic skin material (Lorica soft®) to determine if there was a difference in friction based on interface interaction. Friction testing was completed by sliding a probe across the inside bottom surface of the sock (the part that is usually in-contact with the bottom of the foot) while instantaneously measuring the frictional force every tenth of a second. For both trials (plastic probe and synthetic skin), in the dry condition, knit structure was found to be the most prominate fabric parameter affecting the frictional force experienced at the sock-skin interface. It was also determined that fiber linear density, and yarn type are tertiary factors affecting the frictional force measured at the sock-skin interface. Finally, in the dry state, it was determined that fiber composition had seemingly no effect on the frictional force experienced at the sock-skin interface.