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Stały URI dla kolekcjihttp://hdl.handle.net/11652/4411

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The effect of 3D weft-knitted fabric composition on puncture, tear, and air permeability
(Wydawnictwo Politechniki Łódzkiej, 2022) Krauledaitė, Julija; Ancutienė, Kristina; Krauledas, Sigitas; Urbelis, Virginijus; Sacevičienė, Virginija
This study investigates the influence of 3D weft-knitted fabric fibre composition on the risk of puncture and tear and evaluates the air permeability of these protective knits. For this purpose, different 3D weftknitted fabrics, consisting of outer (protective), binding, and inner (suitable for contact with skin) layers, were produced on an E20 circular weft-knitting machine using different quantities of high molecular weight polyethylene (HMWPE) (from 49% to 24%) and inorganic yarns (from 0% to 23%) in the outer layer while the quantity of polyester in the inner layer and polyamide in the binding layer was kept the same. The puncture and tear resistance tests were conducted to determine the resistance of the 3D weftknitted fabrics to mechanical risks. The air permeability test was performed to assess the comfort properties of the protective 3D weft-knitted fabrics. According to the puncture and tear resistance testing results, it was determined that the highest HMWPE percentage content in the outer layer of 3D weftknitted fabric provided the highest resistance to these mechanical risks. Based on the air permeability test results, it was found that knit with the highest inorganic yarns content in the outer layer achieved the highest air permeability value.
Functional properties of nonwovens as an insulating layer for protective gloves
(Wydawnictwo Politechniki Łódzkiej, 2022) Gorjanc, Dunja Sajn
The basic aim of research presented here is to analyse the influence of the incorporated microporous membrane and the technology of needling process on the functional properties of nonwovens developed as an insulating layer for protective gloves. The studied nonwovens are produced with carded web formation and mechanically bonded with needle bonding. The nonwovens studied contain a microporous membrane of PES with a thickness of 20 μm (samples ST and STL). The experimental part of the present work deals with the mechanical properties: Breaking stress and elongation as well as elastic recovery after cyclic loading. The permeability properties (air permeability) and thermal conduction are also analysed in the experimental part. Research results show that the samples ST and STL, which contain a microporous PES membrane, have a higher breaking stress than the samples T and TL without the microporous PES membrane. Samples ST and STL also show higher values of breaking elongation than samples T and TL. Samples ST and STL are mechanically bonded to the lamella plate using forked needles and therefore have a structured (ribbed) shape that affects the improved mechanical properties. The TL and STL samples, which contain a microporous PES membrane, have higher elastic recovery and lower air permeability than the T and TL samples.
Predicting air permeability of pile loop knit fabrics using fuzzy logic with type-2 fuzzy inference system
(Wydawnictwo Politechniki Łódzkiej, 2022) Haroglu, Derya
Recent studies have shown that pile loop knit fabrics hold promise for being used in tissue engineering in addition to their usual application areas (e.g., sportswear). Understanding the air permeability property of fabrics would be of importance in terms of time and cost when designing new fabrics. This study develops a Fuzzy Logic (FL) model with type-2 fuzzy inference system for predicting the air permeability of pile loop knit fabrics. For this purpose, pile loop knit structures with different areal densities were produced by using textured polyethylene terephthalate (PET) yarns from four different filament fineness. FL model with type-2 sytem analysis was performed. The root mean square error (RMSE) of the developed model was compared with those of the Multiple linear regression (MLR), FL model with type-1 system, and Artificial Neural Network (ANN) model from the previous study. The RMSE of the MLR, FL model with type-1, and type-2 sytems, and ANN were found to be 14.93, 12.41, 11.58, and 2.42 respectively. Thus, the FL model with type-2 system gave less RMSE in comparison to the MLR, and FL model with type-1 system. However, the ANN model provided superior performance over the MLR and FL models in predicting air permeability.