The present study focuses on the preparation and characterization of a poly(ether ether ketone)/poly(ether imide) [PEEK/PEI] blend for application in additive manufacturing using fused filament fabrication (FFF). Polymer miscibility was evaluated using differential scanning calorimetry analysis and Fourier transform infrared analysis. The results confirmed the full miscibility of PEEK and PEI at all compositions. Seen as the best compromise between mechanical properties and glass transition temperature, a 70/30 wt/wt% PEEK/PEI blend was extruded into filaments for use by FFF. Nozzle temperature, layer orientation, and layer thickness were selected as printing parameters to evaluate their effect on the tensile properties and degree of crystallinity (\({{X}}_{\mathrm{c}})\). Optimum printing parameters were achieved at 380 °C nozzle temperature, a [0/15/−15°] layer orientation, and a 0.15 mm layer thickness. The printed PEEK/PEI samples were annealed at various temperatures to erase residual thermal stress generated during printing. Samples annealed for two hours at 200 °C have improved elastic modulus by 21.6%, while \({{X}}_{\mathrm{c}}\) increased by 24.3%. Adding 30 wt% of PEI to the semicrystalline PEEK yielded three advantages, namely improving the operating and service temperatures by 20 °C, decreasing the processing temperature by 20 °C while maintaining most of the high tensile properties of PEEK.

Graphical abstract

中文翻译：

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用于熔丝制造的聚（醚醚酮）/聚（醚酰亚胺）[PEEK/PEI]共混物的制备和表征

本研究的重点是聚（醚醚酮）/聚（醚酰亚胺）[PEEK/PEI] 共混物的制备和表征，用于使用熔丝制造 (FFF) 的增材制造。使用差示扫描量热分析和傅里叶变换红外分析评估聚合物混溶性。结果证实了 PEEK 和 PEI 在所有组合物中的完全混溶性。作为机械性能和玻璃化转变温度之间的最佳折衷方案，70/30 wt/wt% PEEK/PEI 混合物被挤出成细丝供 FFF 使用。选择喷嘴温度、层取向和层厚度作为印刷参数，以评估它们对拉伸性能和结晶度的影响 ( \({{X}}_{\mathrm{c}})\). 在 380 °C 喷嘴温度、[0/15/-15°] 层取向和 0.15 mm 层厚度下实现了最佳印刷参数。印刷的 PEEK/PEI 样品在不同温度下退火，以消除印刷过程中产生的残余热应力。在 200 °C 下退火两小时的样品的弹性模量提高了 21.6%，而\({{X}}_{\mathrm{c}}\)增加了 24.3%。在半结晶 PEEK 中添加 30 wt% 的 PEI 产生了三个优势，即将操作和使用温度提高 20°C，将加工温度降低 20°C，同时保持 PEEK 的大部分高拉伸性能。

图形概要