Improvement of thermal and acoustic properties of fabrics produced by bicomponent foam yarns

In this thesis, low-density polyethylene polymer foam was used for the first time in the production of synthetic yarn. Bicomponent fiber production technique, which is one of the innovative fiber production technologies, was used in the production of the yarns. Polymer foams are used in many industries due to their advantageous properties such as low density, porous structure, low thermal conductivity coefficient, and good sound absorption properties. To benefit from these properties in the field of technical textiles, it was used as an additive in the bicomponent yarn, and the properties it gave to the bicomponent yarns, and the surfaces produced from these yarns were examined. In the production of core/ sheath bicomponent yarns, low-density polyethylene foam was used at the core section with three different additive ratios, and polypropylene polymer was used at the sheath section. The properties of bicomponent yarns were tested with physical tests such as yarn count, tenacity, and elongation, as well as characterization methods such as scanning electron microscopy and differential scanning calorimetry. To examine the thermal insulation and acoustic properties of bicomponent yarns, knitted fabrics were produced from bicomponent yarns. In addition to the physical properties of knitted fabrics such as thickness and weight, thermal conductivity coefficients according to two different standards and sound absorption coefficients were determined. In addition, the results obtained from yarn and fabric samples were subjected to statistical analysis. With the increasing foam polymer additive ratio, the thermal conductivity coefficients of the fabrics decreased, and the sound absorption coefficients increased. The lowest thermal conductivity coefficient was obtained as 0,060 W/mK with the fabric produced with the highest additive ratio. Similarly, the sound absorption coefficient increased by 64% in the fabric with the highest additive ratio.