Structure and mechanical behaviors of thermoplastic polyurethane thin film coated polyamide 6 fibers part II. A solution coating method

Thermoplastic polyurethane thin film (TPU) coated PA6 fibers were prepared by dipping fibers into a TPU solution. The thickness of the thin film coating was 20 μ m. A series of polymer glycols which include polycarbonate, polyether and polyester were used for the preparation of the TPU. Both tensile strength and elongation at break of the TPU coated fibers increased although both magnitudes of the TPUs are much lower than for the original PA6 fibers. Also there was a significant improvement in the abrasion resistance TPU coated PA6 fibers. The PA6 fibers are prone to micro-cracks when under mechanical stress but the TPU thin film coating delayed the formation of the micro-cracks, thereby improving the mechanical properties of PA6 fibers. The theoretical investigation on the effect of interface interaction region using the viscous flow model described could clearly explain the effect of the same on the mechanical performance of TPU coated PA6 fibers.