Complex Yarns Research Articles

Preparation of heterogeneous acetate-kapron and triacetate-lavsan yarns

For rational use of man-made fibres, in many cases it is advisable to use combinations of them in the form of heterogeneous complex yarns. The purposes of such mixing are diverse: improvement in the mechanical and operational properties of articles, expanding the assortment of yarns, economic considerations, and the like. Most often, the manufacture of heterogeneous yarns is dictated by a tendency to compensate for the defects of one component with advantageous properties of the other.

21—The Dynamic Tensile Mechanical Properties of Textile Filaments and Yarns

The apparatus and procedure used in measuring the dynamic properties of twenty-three textile yarns and their dependence on static and dynamic strain are described. Measurements were made between 25 and 350 cycles per second. The specimens behaved non-linearly ; in general, the dynamic Young's modulus increased with static strain and decreased with increasing dynamic strain, while the loss-angle tangent decreased with static strain but increased with dynamic strain. With the more complex yarn structures, the greater part of the variation with dynamic strain can be attributed to inter-fibre slippage. It is expedient to use equivalent linear moduli, and a solution of a non-linear differential equation is given which enables the accuracy with which the equivalent linear moduli represent the energies and stresses in the yarn to be estimated.