Elasticity of woven fabrics made of polytri-methylene terephthalate/ polyethylene terephthalate bicomponent filaments

Abstract

Polytri-methylene terephthalate (PTT)/polyethylene terephthalate (PET) filaments are self-crimping, highly elastic polyester bicomponent fibers. In this paper we studied the influences of important structural variables on the elasticity of woven fabrics made of PTT/PET weft filaments by testing 33 samples with different weave structures, PTT/PET contents, weft densities, and yarn twists. Fabric elasticity is described by two parameters: fabric strain and resilience in tensile testing. The experimental results indicate that twill and satin weaves have greater potentials in obtaining high elasticity than a plain weave. Fabric elasticity increases with the increase of the PTT/PET content in the weft yarn, but the change becomes insignificant after the PTT/PET content exceeds 66.7%. Increase in weft density has a negative effect on fabric elasticity, while the weft twist limits crimp formation of PTT/PET filaments and thus undermines the fabric’s elasticity noticeably. The PTT/PET filaments in fabrics can only realize about 6% of the elastic potential of the original PTT/PET filaments, because the crimp configurations of the filaments are dictated by not only the shrinkage differential of the two components, but also the weave structure and the yarn twist.