Commingled and Air Jet-textured Hybrid Yarns for Thermoplastic Composites

Hybrid yarns have reinforcing and matrix-forming filaments combined together in order to reduce the problems associated with high melt viscosity of thermoplastic matrices. Among hybrid yarns, commingled and air-textured yarns, which are produced with air jets have demonstrated high flexibility and good mixing of constituent filaments. Many research findings have been reported on the structure and properties of intermingled and air-textured yarns having low-modulus apparel-grade filaments. The relationships between air jet, filament yarn, and the processing parameters are critically reviewed. It is emphasized that there is an immediate need to study the mixing behavior of combination of high- and low-modulus filaments in air jet, which has not been investigated in detail in the published literature, in order to improve the mixing of these filaments. The methods used to characterize hybrid yarns are discussed. The need to study and improve the stability of the hybrid yarns in terms of maintaining the level of mixing of constituent filaments across the cross section is also established.