Ten types of polyester fibres in industrial use from various domestic and overseas factories were used in this study.The detail structure of filaments has been analyzed by the data measured from small angle X-ray scattering

wide angle X-ray diffraction

density and birefringence.In addition

hot air shinkage properties of filaments were measured.Then the relations between microstructure and macroscopic shrinkage properies were discussed.The results showed that the A cX Lfvc/fa of generalized structure parameters can summarize the structure factors influencing thermal dimensional stability primarily.The emphasis was on the important role of perfection of crystals and the"degree of continuity" and the perfection of the network of crystalline elements.