Search results for "Yarn"
showing 4 items of 24 documents
Study regarding the physical-mechanical properties of knits for garments – pilling performance
2017
The effect of the pilling degradation results is an important decreasing in garment quality and a negative influence on the user’s comfort to wear. There are a lot factors, such as the yarn spinning system, fabric geometry and finishing operation, which affect the pilling performance. This research paper presents the investigation of fabric surface concerning pilling formation, especially knits, influenced by the fibrous composition. As samples were used knitted fabric panels, obtained from carded yarns, with fibers composition like cotton, wool or mixed one. Regarding fabric geometry 3 types were used – single jersey, 2x2 rib and moss stitch. In order to establish which of the yarns are mo…
Mechanical Behavior of Concrete Columns Confined by Laterally Pre-Tensioned FRP
2011
This paper presents the results of an experimental investigation of concrete columns confined by a wound pre-tensioned carbon filament yarn. Yarn winding equipment was developed in the Institute of Polymer Mechanics with the ability to set the desired pre-tension force and thereby producing confined concrete specimens with different initial lateral pressure. It is shown that initial lateral pressure increases the axial stress at which intense internal cracking of the concrete develops.
Thermal and Mechanical Characterization of Yarn Samples from Flemish Tapestry of the Sixteenth Century
2022
We propose a physico-chemical approach for theharacterization of the conservation condition of yarns from a Flemish tapestry of the sixteenth century. The aging effect on the yarns’ performance was evaluated by comparison with commercial materials. Water uptake experiments highlighted the aptitude of yarns toward water sorption and their increased hydrophilicity upon aging. Thermogravimetric analysis can be considered a fast approach for the fiber identification and assessment on the material life-time. The dynamic mechanical analysis provided direct evidence on the yarns, conservation state and their performance under different mechanical stresses. The proposed characterization path can be…
Functional Bionanocomposite Fibers of Chitosan Filled with Cellulose Nanofibers Obtained by Gel Spinning
2021
Extremely high mechanical performance spun bionanocomposite fibers of chitosan (CHI), and cellulose nanofibers (CNFs) were successfully achieved by gel spinning of CHI aqueous viscous formulations filled with CNFs. The microstructural characterization of the fibers by X-ray diffraction revealed the crystallization of the CHI polymer chains into anhydrous chitosan allomorph. The spinning process combining acidic–basic–neutralization–stretching–drying steps allowed obtaining CHI/CNF composite fibers of high crystallinity, with enhanced effect at incorporating the CNFs. Chitosan crystallization seems to be promoted by the presence of cellulose nanofibers, serving as nucleation sites for the gr…