This study revealed the effect of cam setting and number of yarn ply on air permeability and bursting strength of weft-knitted fabrics from glass yarn. Change in cam setting from loose to tight level increased fiber content, and stitch-density; while it decreased loop length. Fabrics with 3-ply yarn exhibited higher fiber content; lower stitch-density; and longer loop length than fabrics with 2-ply yarn. Cam setting showed more pronounced effect on physical properties of fabric than number of yarn ply. Fabrics knitted via tight cam setting level exhibited less air permeability, and higher bursting strength than fabrics knitted via loose cam setting. Fabrics from 3-ply yarn showed less air permeability and higher bursting strength than fabrics from 2-ply yarn. Loop length, wale density, and fiber content were determined as the most effective physical properties on permeability and bursting strength. A negative correlation was detected between air permeability and bursting strength.

In this study; the effects of loop, skip, and tuck stitch types, and weft-inlay yarn, on air permeability and bursting strength of weft-knitted fabrics from glass yarn were revealed. Due to clockwise rotation of wales and their arrangement being one on top of the other, besides the dramatic shortening of fabrics after their removal from the machine; fabrics with tuck stitches exhibited the highest stitch density, fiber content, and the shortest loop length. This caused the lowest air permeability and the highest bursting strength. Contrary to expectations, weft-inlay yarn did not contribute to bursting strength as much as tuck stitch did. An overall negative correlation between air permeability and bursting strength was disrupted by structures with tuck stitches. While tuck stitches from cotton yarn increased air permeability and decreased bursting strength in previous studies; this study indicated that tuck stitches from glass yarn decreased air permeability and increased bursting strength.

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In this study, polyester matrix composites reinforced by 1x1, 2x2, half- and full-cardigan rib pattern weft-knitted fabrics from glass and glass/aramid hybrid yarns were produced. Tensile, flexural and impact tests were applied to the composites. The 2x2 rib pattern composite showed the highest thickness and density. The hybridization of glass yarn with aramid yarn increased the thickness, while it decreased the density of composites. The 2x2 rib pattern composite showed the highest tensile modulus and tensile strength. Yarn hybridization increased tensile strength at statistically significant level. The composite with full-cardigan rib pattern displayed considerably higher flexural modulus and flexural strength than the composites with the other patterns. When glass and hybrid composites were considered separately, the rib fabric pattern exhibited significant effect on maximum load. The rib fabric pattern displayed also significant effect on absorbed energy for glass composites. The yarn hybridization dramatically increased maximum load and absorbed impact energy.