Compressibility and air permeability of weft knitted rib fabrics from glass yarn

Expandable, intermeshed, three dimensional, porous weft-knitted fabrics manufactured on double-bed knitting machines have numerous technical application areas (comfortable protective clothing, chemical and flame resistant filter media, and impact resistant polymer matrix reinforced composite reinforcement); as they are knitted from high performance fibers such as glass, carbon and aramid. The performances of these fabrics in technical application areas depend on the fabric porosity (or fiber volume fraction) that is primarily dictated by the knit pattern (pattern), and quantified by permeability of the fabric to air. In this study, weft knitted fabrics with 1x1, 2x2, English, and fisherman rib patterns from 3-ply E-glass yarn with a nominal single-end yarn count of 136 Tex were manufactured. A manual, flat, double-bed weft knitting machine with a fineness of 5E was used to knit the fabrics. Thickness (compression, and relaxation), areal density, course-density, wale-density, loop length, and air permeability of the fabrics were measured. The effects of knitting pattern on the physical properties of the fabric with air permeability and compressibility have been studied.