Engineering knits for versatile technical applications: Some insights on recent researches

Knits have been playing a predominant role in the area of technical textiles, as recent researches point out. In one of the areas, knits have been produced for advanced textile preforms, wherein they have been knitted into net shapes and have advantages such as high conformability/drapeability to accommodate complex shape moulds, and good permeability. The advanced composite manufacturing processes demand the use of fashionable near net-shaped preforms. Flat knitting technology is especially suited for the production of such products like biaxial-reinforced multi-layer weft-knitted fabrics. Also, natural fiber knits have been developed using flat weft knitting technology in geo textiles, wherein the fabrics could be designed to suit varied soil types and conditions. These have indeed proved to be more economical and superior to their synthetic counterparts. Recently, knit scaffolds made from Poly Lactic Acid (PLA) yarns have been developed for urinary bladder reconstruction. They hold promise for other medical applications such as cardiovascular prosthesis and compression bandaging. Fabrics have been knit with copper core yarns and evaluated for their electromagnetic shielding effectiveness. The shielding effectiveness has been found to increase with factors such as tightness, wale density, and course density. Also, the interlock knitted fabric has better electromagnetic shielding effectiveness in comparison with rib and plain knitted fabrics. Warp knit coupled with stitch bonding technology has been able to effectively produce reinforcement textiles for composite materials. In yet another interesting development, weft knit and braided polypropylene has been used as stents for treating cardiac arterial diseases. The knit stents have proved to be advantageous over the metallic ones with regard to flexibility and easy movement. Warp knits have also been used for large-scale structures as in aircraft applications.