Study On The Structure And Properties Of New Polyester Fibers And Fabrics

Synthetic fibers have a great progress in 20th century as an important part of textile materials. Polyester fibers have become the largest amount in textile fibers because of their excellent properties and lower price. The general properties of PBT fibers are more excellent than PET fibers, and PTT fibers have both PBT and PET fibers fine properties. As elastic sub-elastic fibers, they are more excellent on the performance to price than Lycra? So they are worth being studied as far as economy and properties are considered. But there are some problems on their commercial products and practicability especially how to achieve elastic and puff. It is necessary to research the fibers which have reasonable price and can be easily made to fabrics. This thesis mainly concerns the investigation on the structure and properties of side-by-side PBT/PET fibers and their fabrics in order to enlarge polymer fibers' application fields, enhance their value and make elastic and bulk fabrics.The structures and properties of PBT/PET composite fibers and PTT fibers, as well as their fabrics have being discussed in detail through a series of experiment. Several effective results and conclusions have been achieved as follows:1. By the optics microscope and SEM, the crimp morphology, cross-sectional shape and fracture ends of PBT/PET composite fibers are studied. Based on the observations, the feasibility to combine PBT and PET together and the mechanism of rupture are discussed. At the same time, the functions of PBT and PET in the PBT/PET side-by-side fibers are analysed.2. The relationships between crystal the fiber component or ligation and the spinning technologies are studied by using IR microscope and DSC. The individed functions of PBT and PET have been proved.3. The shrinkages in water and dry of the complex polymer fibers are tested through a great deal of experiments. The shrinkage behaviours of the composite PBT/PET fibers are analysed by means of linear regression method.4. The crimp model of PBT/PET fiber has been set up. The crimp parameters of the PBT/PET fibers are measured using a crimp tester, and the relationship between crimp properties and fibers structure is characterized. By using the Instron tensile instument, the mechanical properties of PBT/PET fibers were tested. At the same time, the representative tensile curves in stretching are obtained. Based on this results, we can discuss the relationship between the mechanical properties and the structure of the fibers.5. The fabric properties knitted with the PBT/PET fibers were tested systematically, especially the bulk property and elasticity of these fabrics. The regression relationships between the fibers and the knittings have been established.