Fabrication and mechanical properties of self‐reinforced polyester composites by double covered uncommingled yarn

Self‐reinforced poly(ethylene terephthalate) (srPET) composites composed of double covered uncommingled yarn that was prepared through cowrap spinning were hot pressed using a film stacking technique. The optimal consolidation temperature for manufacturing lamina was determined to be 240°C and resulting in the adequate impregnation and reinforcing structural integrity. The srPET laminates that had a plain structure exhibited the excellent tensile responses, whereas those with a twill weaving structure had the highest impact energy absorption. In the plain fabric, there were more interlace points and a higher crook degree of wrap and weft yarns in the periodic unit cell, resulting in more clamp force on the yarns at the interlace points during stretching and more elongation. The srPET composites prepared using basket‐weaving structural fabric broke apart and resulted in the lowest impact energy, which can be attributed to the larger gap between two interweaving points that creates a weak path. A strong influence from the weaving structure was observed for the α relaxation of the composites. T_α shifted to a higher temperature because the reinforcing of the fibers and the structural integrity was more effective. POLYM. COMPOS., 37:3331–3340, 2016. © 2015 Society of Plastics Engineers