PEEK yarns are used for commingled yarn based preforms in order to manufacture high performance thermoplastic composites. In a previous work, characterizations of PEEK commingled yarns revealed degradation, causing poor consolidation of final composites. The sizing applied onto the yarn surface in the melt spinning was identified as a degradation factor. Thus, the aim of this work is to assess the effect of different melt spinning parameters: extrusion, sizing and draw ratio, on PEEK integrity and its degradation process. Yarns at different stages of melt spinning were characterized through various techniques. For all yarns, degradation was identified during further transformation, in the molten state, inducing a decrease of the crystallization temperature and an increase of viscosity due to crosslinking. Extrusion initiates degradation earlier without changing the PEEK decomposition process. Sizing is responsible for an acceleration and modifications of degradation steps.

PEEK 纱线用于混合纱线预制件，以制造高性能热塑性复合材料。在之前的工作中，PEEK 混纺纱线的特性表明其降解，导致最终复合材料的固结不佳。在熔纺中施加到纱线表面的上浆被确定为降解因素。因此，这项工作的目的是评估不同熔体纺丝参数（挤出、上浆和拉伸比）对 PEEK 完整性及其降解过程的影响。熔体纺丝不同阶段的纱线通过各种技术进行表征。对于所有纱线，在进一步转变过程中发现降解，在熔融状态下，由于交联导致结晶温度降低和粘度增加。在不改变 PEEK 分解过程的情况下，挤出会更早地引发降解。尺寸调整负责降解步骤的加速和修改。