- ItemSTANDARDISING THE SAMPLE PREPARATION FOR ANALYSIS OF FIBRES AND PARTICLES BY STATIC IMAGE ANALYSIS(Technical University of Liberec, ) FISCHER, HOLGER; SIGMUND, INA; HARTWIG, PETRA; DEDERER, ESTHER; MASCHINSKI, ANNETT; Technická univerzita v LiberciStatic image analysis is known as a versatile method, which is in use for characterisation i.e. of fibres, nonwovens, textile recyclates etc. Due to incomplete standardization (esp. in the area of sample preparation) the usage is actually limited. Within the project StaPAFaB two research institutes are engaged to compile a reference manual listing typical classes of materials and optimised methods of sample preparation for each of them. This will be combined with recommendations for reasonable parameters in image acquisition / processing and possible limitations for each type of material. Aim is to enable reproducible and consistent analyses on an inter-laboratory level as well as to reduce the demand of time for the analyses. This article focuses on typical classes of textile materials and adapted methods to enable their quick and reliable sample preparation.
- ItemSURFACE ROUGHNESS OF POLYAMIDE KNITTED FABRICS(Technical University of Liberec, ) TOMOVSKA, ELENA; HES, LUBOS; Technická univerzita v LiberciFabrics are never ideally smooth. Their texture varies between fine and coarse, quantified through the surface’s vertical deviation. Fabric roughness, or its opposite smoothness, is employed as measure of the surface texture of fabrics. In general, texture depends upon fiber properties, yarn count, yarn twist, and fabric structure and fabric design). This research aims to determine the limitations in visual perception of surface roughness in comparison to objective surface roughness measurements of low weight polyamide fabrics. Subjective evaluation is used for the visual assessment, while instrumental measurement of the properties was conducted using a noncontact laser profilometer. Subjective evaluation was conducted by a panel of forty untrained evaluators on a sample of seven polyamide knitted fabrics with different yarn count and composition. The roughness profile parameters were measured using Talysurf CLI 500 according to ISO 4827. Although the surface roughness measured as arithmetic mean deviation (Ra) and roughness through visual inspection of the fabric are correlated, instrumental measurements of roughness are more precise. Differences in the surface roughness arising from significantly different yarn structures will be observed, while those due to the knitted fabric structure are negligible in visual inspection.
- ItemINVESTIGATION OF STRUCTURAL AND PERFORMANCE PROPERTIES OF HEMP-CONTAINING KNITTED FABRICS WITH DIFFERENT COMPOSITIONS(Technical University of Liberec, ) SEN, KORHAN; KAYA, AYSEGUL; KANIK, GOKSU; Technická univerzita v LiberciThe growing relevance of sustainable materials has increased the importance of hemp-containing products obtained from natural fibers. When the raw materials used in the garment industry are examined, it is observed that the market share of hemp-containing fibers is low in percentage. Researching the production techniques and methods of fabrics to be obtained from hemp fiber and adapting them to the use of clothing will contribute significantly to the development of the hemp product range. It is aimed that these fabrics to be developed will pass tests in accordance with end-consumer standards. In this study, structural and performance properties of hemp fiber were examined and alternatives were produced instead of conventional methods for a sustainable world. In line with the sustainability strategy, there are advantages of hemp fibers in terms of water consumption, environmental impact compared to cotton fiber. Within the scope, studies were carried out to develop single jersey knitted fabrics by hemp- containing at different compositions such as 70 % cotton/ 30 %hemp, 80 % cotton/ 20 %hemp and 90 % cotton/ 10 %hemp, %100 cotton fabric having the similar structural properties was taken as a control sample. As a result, prototype tests were performed considering the structural and performance properties of the developed fabrics.
- ItemIDENTIFYING THE MATERIALS IN ARCHAEOLOGICAL TEXTILES(Technical University of Liberec, ) BŘEZINOVÁ, HELENA; PECHOČIAKOVÁ, MIROSLAVA; GRABMÜLLEROVÁ, JANA; Technická univerzita v LiberciGiven their organic origin, textiles rank among the rarest archaeological finds. While the vast majority of these artefacts are preserved as small fragments or mineralised remnants, their detailed textile technology study provides interesting and important information about the use of textile techniques and the quality of processing. The most important information concerns the utilised textile materials, but for degraded textiles, these materials are among the most difficult information to obtain. Image analysis using electron microscopy (SEM) is a significant aide in this pursuit.
- ItemPOLYACRYLONITRILE NONWOVENS FOR THE PRODUCTION OF CARBON MATERIALS SUPPORTING THE REGENERATION OF BONE AND CARTILAGE TISSUES(Technical University of Liberec, ) BOGUŃ, MACIEJ; ŚLEDZIŃSKA, KATARZYNA; GIEŁDOWSKA, MAŁGORZATA; KRÓL, PAULINA; KAMIŃSKA, IRENA; MAGDZIARZ, SYLWIA; Technická univerzita v LiberciThe influence of the change in surface weight on the physical properties of oxidized polyacrylonitrile precursor nonwovens intended for the production of carbon materials used in tissue engineering was studied. Thermal insulation properties of the nonwovens and their behavior during incubation in phosphate buffered saline (PBS) were investigated. Initial carbonization tests showed that from the point of view of carbonization and further application of carbon materials, the most effective was the use of a surface weight of about 120 g/m2. At the same time, for the research conducted on the incubation of nonwovens in PBS, no significant change in the pH of the solution was found.