Abstract This work provides a novel approach to manufacture hierarchical porous parts via an in-situ foaming fused deposition modeling (FDM) method. The cell nucleation, growth, and stabilization occurred as the CO2-saturated polyetherimide (PEI) filament was heated, and the layer-by-layer deposition of porous strands was controlled by a planned path. The microporous structure with cell size of 2–30 μ m and cell density of 1010−11 cells/cm3 was generated inside and on the surface of the porous PEI strand, and the macroporous structure with size of about 1–50 mm was constructed within the porous PEI honeycombs and cylinder. The compressed CO2 exhibited extremely slow diffusivity in PEI filaments, and the stable CO2 content ensured that the hierarchical porous PEI part could be 3D printed with high accuracy for a long time.

中文翻译：

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原位 CO2 发泡技术辅助分层多孔聚醚酰亚胺的熔融沉积建模

摘要 这项工作提供了一种通过原位发泡熔融沉积建模 (FDM) 方法制造分层多孔部件的新方法。随着 CO2 饱和聚醚酰亚胺 (PEI) 灯丝被加热，细胞成核、生长和稳定发生，多孔线的逐层沉积由计划路径控制。在多孔 PEI 链的内部和表面上产生了细胞尺寸为 2-30 μm 和细胞密度为 1010-11 个细胞/cm3 的微孔结构，并在其内部构建了尺寸约为 1-50 mm 的大孔结构。多孔 PEI 蜂窝和圆柱体。压缩后的 CO2 在 PEI 长丝中表现出极慢的扩散性，稳定的 CO2 含量确保了分层多孔 PEI 部件可以长时间高精度地 3D 打印。