The Effect Of Yarn Structure On The Fire Retardant Properties Of Conex Blended Yarns

In the wake of the consequent injury, loss of life and property, flame/fire retardant (FR) textiles have assumed an increasingly important role in the provision of protection against the hazard brought about by uncontrolled fires. The textile and other allied industries have had to focus research efforts on the area of minimizing the risk and loss posed by uncontrolled fires. Consequently, textiles were and are still being chemically modified to impart on them FR properties. In usage however, some of these modified textiles have shown drawbacks and hazards to human health. This hazards and drawbacks have kept the focus in research on FR textiles. The focus has therefore shifted to fibres with chemical structures that impart FR properties on the resultant textiles, the so-called inherently FR textiles.The development of the manufacture and application of FR textiles is reviewed. Also reviewed is the application of various FR textiles in China and in Kenya.The research recorded in this thesis is a continuation of the research on inherently FR textiles. The purpose of the research is to determine the yarn parameters that give the best FR performance.Conex FR fibre developed by Teijin Limited of Japan is the main subject of experimental study. The spinning of pure conex is studied. Blends of conex and other FR fibres are also spun to experimentally test classical theories on blended yam properties and fibre distribution in blended yarns. Basofil fibre developed by Basf company of Germany is also featured.It is demonstrated that it is possible to obtain a required fibre distribution in a blended yarn when friction spinning is employed. A number of cross-sectional fibre distributions are engineered.An argument for the testing of FR properties in yarn in place of fabrics is presented and a test method for testing of the FR properties of yams is proposed. The influence of various factors on the FR properties of yams is thereafter investigated.The spinning variables; spinning method, twist level, radial fibre arrangement, are also shown to have an influence on the FR properties of yams and fabrics. It is shown that although the ring-spinning method gives the best performance, it has a disadvantage in the twist requirement for production; it is shown qualitatively that the twist has a direct effect on the FR performance of the yams spun. In radial fibre distribution for a blend of conex and viscose, a distribution of conex fibre in the core and surface (with viscose fibre on the middle zone) is shown to impart optimum FR properties to the yarn and the fabric woven thereof.It is concluded that friction spinning may be used for the cost-effective manufacture of fabrics for FR use.