The work is devoted to the study of the geometric parameters of a knitted loop. It has been found that the optimal model is a loop model detailed at the yarn level, which considers the change in the cross-sectional shape and sets the properties of the porous material in accordance with the internal porosity of the yarn. A mathematical description of the coordinates of the characteristic points of the loop and an algorithm for calculating the coordinates of the control vertices of the second order spline, which determine the configuration of the yarn axes in the loop, are presented in this work. To create 3D models, Autodesk AutoCAD software and Structura 3D software, developed in the AutoLisp programming language, were used. The simulation of the air flow process was carried out in the Autodesk CFD Simulation environment. For the experimental investigation, plane knits from 44 tex × 3 linear density ultra-high molecular weight polyethylene yarns were produced, and their air permeability was tested according to Standard DSTU ISO 9237:2003. The results obtained during the laboratory experiment and simulation differed by less than 5%.

Analysis of functional products for medical textiles indicates that there are plenty of different classifications of this group. Requirements for compression generated by compression garments differ depending on the application area, and even more, sometimes are contradictory and can be fulfilled in very different ways. The effectiveness of such products depends on mechanical and physical properties as well as psychological barriers. Currently, there is no uniform classification of compression classes, furthermore, there is no uniform standard, test method or technic for evaluation of the product’ compression. Knitted compression fabrics are made by knitting together at least two types of yarns: a ground yarn which ensures stiffness and thickness and an elastomeric yarn which generates compression. Knitted compression products can be produced on both flat and circular knitting machines, though parameters and usage of production are different. Additional elements used in the structure of the compression product can significantly change the generated compression. Purposes and number of additional details depend on the application and functionality of the compression support, nevertheless, all rigid elements must be taken into account at the designing stage. Additional functionality like antimicrobial activity or thermal therapy can also be provided for compression knits. It is highly important to ensure the longevity of all functional properties.

This work presents a simple and flexible method for theoretical calculation of the main structural parameter of weft-knitted fabrics’—the loop length and one of the main characteristics of textile fabrics—area density, which combines physical and economical aspects. It helps to predict many physical properties and the mechanical behaviour, which is especially important for protective textiles, and allows predicting potential yarn consumption for knitting of one square meter of the fabric. The main idea of the proposed method, based on Čiukas geometrical model, is to calculate different parts of the knitted loop separately, which gives a great flexibility of such modelling. The proposed theoretical formulas can be used for various weft-knitted structures, give very low errors to empirical calculations, and are easy to use. It is a big advantage because known geometric models only allow a loop length of some particular pattern to be calculated, usually of single jersey or rib 1 × 1.

This work focused on the development of ultra-strong knitted fabrics for personal protective equipment used for protection against mechanical damages. Such knits have to have enhanced mechanical strength properties, which strongly depend on knitting pattern and structural characteristics. Six variants of weft knitted structures were developed and knitted from ultra-high molecular weight polyethylene and additional elastomeric component. The elastomeric component was used to increase the elasticity and toughness of knits; however, it had a high influence on mechanical properties, as well. The performed mechanical tests allowed us to identify dependence of mechanical properties, such as breaking force and elongation at break and resistance to abrasion, tearing, cutting and puncture, on architecture and structural parameters of the knits. Obtained results demonstrate that elastomeric component has high influence on mechanical properties knits and can change the principal mechanical behaviour of knits.

Compression therapy can be successfully applied to the treatment of amputated limbs. Compression is known to speed healing and reduce the appearance of complex scars. This is particularly relevant as the number of amputations increases, especially during times of war, such as the current war in Ukraine. For the research presented in this article, compression knits of two pattern repeats and twelve structural variations each were created. We investigated how the compression generated by the knit is influenced by the main factors which theoretically could have an effect: knitting pattern, density of loops, speed of the wheel supplying elastomeric inlay-yarn into the knitting zone, and elongation resulting from the difference between the knitted limb cover and limb circumference. It was found that in the area of low elongations (up to 50%) of the investigated elastomeric knits, the speed of supply of the inlay-yarn does not have a significant influence on the compression. However, the effect of loop density and knitting elongation on the generated compression is significant and manifests linearly. In addition, the established equations can be used for compression prediction and knitting design according to the required compression class.

Last decade a lot of research was done in the development and investigation of textile-based shielding materials against electromagnetic radiation. Still, there is a gap in understanding the effect of knitted structure (i.e., stitch type and shape) on shielding effectiveness by different shielding mechanisms: reflection and absorption. Seven knitted fabrics were produced on 8-gauge flat knitting machines, using 0.12 mm diameter stainless steel (SS) wire and 30 x 2 tex cotton yarn. The fabrics differ by the method of incorporation of conductive element (SS wire) into the knitted structure: separately and simultaneously with cotton yarn and used interloopings. The effect of stitch type (loop, float, or tuck) was studied as well. It was found that both the method of SS wire incorporation and the shape of its positioning in the knitted structure affect the EMR shielding effectiveness while only the method of SS wire incorporation determines the shielding mechanism: absorption or reflection. The half Milano rib knitted structures demonstrate the best shielding efficiency due to the additional floats behind held loops.