Mechanical properties of polypropylene/glass weft knitted composites hot pressed in various structures and contents

In this study, composites of knitted fabric made from side-by-side multiple glass and polypropylene yarns have been investigated. These composites have been produced by a new manufacturing method - the hot press method. By using various knitted fabrics made from different components of glass and polypropylene yarns, several types of knitted structures and yarn components were investigated: rib 1-1, full Milano and full cardigan. The mechanical properties of composites were measured in three directions. The results showed that hot-pressed knitted composites of glass and polypropylene yarns have high strength, impact resistance, work-to-break and elongation, simultaneously. The highest bending resistance and maximum stiffness are achieved for rib-knitted composites consisting of 8 wt% glass and 92 wt% poly propylene yarns. The highest impact energy absorption was obtained with 18 wt% glass content and 82 wt% polypropylene matrix.