Thesis Details

Thesis Title: The effect of blending microdenier and conventional polyester staple on the quality and aesthetics of open-end and air-jet yarns
Thesis Author: Michael Carrigan
Abstract: Microdenier fibers have been, and are still today, the focal point of a great deal of attention. The expectation is that microdenier fibers will continue to grow in popularity. They are known to enhance the appeal of the end products produced with them. Unfortunately, manufacturing difficulties caused by the different characteristics of microdenier fibers (namely more fibers and more pliable fibers) have prevented yarn manufacturers from being able to meet the large demand. It has been proven that difficulties have been encountered in carding (these fibers tend to nep and load on the cylinder). This research was undertaken to determine if blending microdenier fibers with conventional fibers could improve the processability of fine denier fibers, and at the same time improve the aesthetics of rotor and air-jet yarns. To accomplish this work, six different denier conditions were produced (4 mixed and 2 pure) by intimate blending. All conditions were spun on a MJS spinning frame and an Autocoro open-end spinning frame, producing 30/1 yarn. The experimental yarns were knitted, and the fabrics were commercially dyed. The results of the tests conducted were analyzed through variance analysis of a factorial design, and comparisons of individual means. Fabrics containing each fiber variant were also subjected to a paired comparisons analysis for appearance and hand. The levels of the independent variables in the design were as follows: Polyester denier: 50/50 blend of 0.50/1.20 dpf polyester staple (avg. dpf 0.70) 20/80 blend of 0.50/1.20 dpf polyester staple (avg. dpf 0.93) 20/80 blend of 1.20/0.90 dpf polyester staple (avg. dpf 0.93) 50/50 blend of 0.90/1.20 dpf polyester staple (avg. dpf 1.03) 100% 0.90 denier polyester staple 100% 1.20 denier polyester staple Yarn composition: 100% polyester and 65/35 polyester/cotton Testing was conducted at the Institute, and at a member company. The following general results were noted. 1. Although the stock processed well at carding, tests revealed some damage did occur to the 0.50 denier fibers. However, the damage was not as severe as in previous studies. Cardability of the microdenier fibers was improved by blending deniers. 2. The rotor system overcame the problems associated with the damaged fibers. 3. The rotor system benefitted from the presence of microdenier fiber.