Doyle Lucía, Pérez-Ferrero Xabier, García-Molleja Javier, Losada Ricardo, Romero-Rodríguez Pablo, Fernández-Blázquez Juan P
IMDEA Materials Institute, C/Eric Kandel, 2, Getafe, 28906 Madrid, Spain.
AIMEN Technology Centre, O Porriño, 36418 Pontevedra, Spain.
Polymers (Basel). 2024 Nov 29;16(23):3354. doi: 10.3390/polym16233354.
Recent advancements in thermoplastics within the polyaryletherketone (PAEK) family have enhanced additive manufacturing (AM) potential in fields like aerospace and defense. Polyetheretherketone (PEEK), the best-studied PAEK, faces limitations in AM due to its fast crystallization, which causes poor inter-filament bonding and warping. This study investigated alternative, slow-crystallizing PAEK polymers: polyetherketoneketone (PEKK-A) and AM-200, a PEEK-based copolymer. Both can be printed in an amorphous state and then annealed to improve crystallinity and mechanical properties. Despite their potential, these materials have been minimally explored for AM. Our analysis compared the mechanical performance of as-printed and annealed samples and showed that slow-crystallizing PAEKs outperform fast-crystallizing PEEK. As-printed PEKK-A and AM-200 parts reached tensile strengths of 69 MPa and 47 MPa, respectively, which are about 80% of the values for injection-molded parts. In contrast, PEEK achieves only 25% due to poor inter-layer bonding. Annealing increased crystallinity (15.7% for PEKK-A, 19% for AM-200), simultaneously leading to a coalescence of smaller pores into larger ones, which affected mechanical integrity. Annealing strengthened the printed filament direction, while Z-direction strength remained limited by interlayer adhesion. Our work provides new insights into optimizing these relationships to expand the applicability of PAEK in additive manufacturing.
聚芳醚酮（PAEK）家族中热塑性塑料的最新进展增强了其在航空航天和国防等领域的增材制造（AM）潜力。聚醚醚酮（PEEK）是研究最深入的PAEK，但由于其快速结晶，在增材制造中存在局限性，这会导致丝间粘结不良和翘曲。本研究调查了替代性的、结晶缓慢的PAEK聚合物：聚醚酮酮（PEKK-A）和一种基于PEEK的共聚物AM-200。这两种材料都可以在非晶态下打印，然后进行退火处理以提高结晶度和机械性能。尽管它们具有潜力，但这些材料在增材制造方面的探索还很少。我们的分析比较了打印态和退火态样品的机械性能，结果表明结晶缓慢的PAEK比结晶快速的PEEK性能更优。打印态的PEKK-A和AM-200部件的拉伸强度分别达到69 MPa和47 MPa，约为注塑部件强度值的80%。相比之下，由于层间粘结不良，PEEK仅达到25%。退火提高了结晶度（PEKK-A为15.7%，AM-200为19%），同时导致较小的孔隙合并成较大的孔隙，这影响了机械完整性。退火增强了打印丝的方向强度，而Z方向的强度仍然受到层间附着力的限制。我们的工作为优化这些关系以扩大PAEK在增材制造中的适用性提供了新的见解。
