Abstract

Increasing the molecular weight via polycondensation process is an efficient way to improve polyester industrial fiber strength. This paper compares the performance and structures of poly(ethylene terephthalate) (PET) fibers made with solid-state polycondensation (SSP) and liquid-state polycondensation (LSP) processes. Two PET fibers were prepared by melt spinning with SSP and LSP. The structures of the fibers were characterized by wide-angle X-ray scattering (WAXS), small-angle X-ray scattering (SAXS), birefringence and dynamic mechanical analyzers (DMA). The PET fiber with SSP possesses a little larger molecular weight of narrower distribution, greater tenacity, higher crystallinity and orientation, larger lamellar thickness, smaller tilting angle and smaller amorphous layer thickness than that with LSP. The results indicated that although the differences in the molecular weight and its distribution of the fibers made with SSP and LSP are not notable, the microstructures and mechanical properties of the spun HT fibers are quite different.

摘要

通过缩聚工艺增加分子量是提高聚酯工业纤维强度的有效途径。本文比较了采用固态缩聚（SSP）和液态缩聚（LSP）工艺制备的聚对苯二甲酸乙二醇酯（PET）纤维的性能和结构。通过与SSP和LSP熔融纺丝制备了两种PET纤维。纤维的结构以广角X射线散射（WAXS），小角X射线散射（SAXS），双折射和动态力学分析仪（DMA）为特征。与LSP相比，具有SSP的PET纤维具有更大的分子量，更窄的分布，更大的韧性，更高的结晶度和取向，更大的层状厚度，更小的倾角和更小的无定形层厚度。