瓶片与切片级涤纶FDY的结构与性能对比

Contrast of structure and properties of PET FDY from bottle-grade and fiber-grade chips

采用扫描电镜、傅里叶变换红外光谱仪、差示扫描量热仪、X射线衍射仪、热失重分析仪、单纤维强力仪等对瓶片涤纶全拉伸丝(FDY)与切片涤纶FDY的结构与性能进行表征与比较。结果表明:纤维表面均比较光滑,但瓶片涤纶FDY表面存在少量颗粒凸起,在分子结构上两者无明显区别,瓶片涤纶FDY和切片涤纶FDY的结晶度分别为37.86%,37.24%;瓶片涤纶FDY的熔点为240℃,切片涤纶FDY的熔点为260℃;瓶片涤纶FDY的断裂强度为3.638 c N/dtex,切片涤纶FDY断裂强度为3.792 c N/dtex,其力学性能相差不大,但经热处理和日晒后,瓶片涤纶FDY的断裂强度下降程度略大于切片涤纶FDY;瓶片涤纶FDY和切片涤纶FDY都具有较好的染色性能,上染率分别为88%和90%。

The structure and properties of polyethylene terephthalate （PET） fully drawn yarn （FDY） from bottle-grade chip and fiber-grade chip were characterized and compared by scanning electron microscopy, Fourier transform infrared spectrometry, differential scanning calorimetry X-ray diffraction analysis, thennogravimetric analysis, single fiber tensile strength test. The re- suits showed that PET FDY from fiber-grade chip had smooth surface when PET FDY from bottle-grade chip had the surface with a little particle projection, and no obvious difference was observed between their molecular structure; the PET FDY from bottle- grade chip and fiber-grade chip exhibited the crystallinity of 37.86% and 37.24%, the melting point of 240 ℃ and 260 ℃, the breaking strength of 3. 638 eN/dtex and 3. 792 cN/dtex, dye up-take of 88% and 90%, respectively, but they were similar in mechanical properties; the breaking strength of PET FDY from bottle-grade chip was decreased more profoundly than that of PET FDY from fiber-grade chip after heat treatment and insolation.