Herzberger Jana, Meenakshisundaram Viswanath, Williams Christopher B, Long Timothy E
Department of Chemistry and Macromolecules Innovation Institute (MII), Virginia Tech, Blacksburg, Virginia 24061, United States.
Department of Mechanical Engineering and Macromolecules Innovation Institute (MII), Virginia Tech, Blacksburg, Virginia 24061, United States.
ACS Macro Lett. 2018 Apr 17;7(4):493-497. doi: 10.1021/acsmacrolett.8b00126. Epub 2018 Apr 4.
Polyamic acid (PAA) salts are amenable to photocuring additive manufacturing processes of all-aromatic polyimides. Due to an all-aromatic structure, these high-performance polymers are exceptionally chemically and thermally stable but are not conventionally processable in their imidized form. The facile addition of 2-(dimethylamino)ethyl methacrylate (DMAEMA) to commercially available poly(4,4'-oxydiphenylene pyromellitamic acid) (PMDA-ODA PAA) afforded ultraviolet curable PAA salt solutions. These readily prepared solutions do not require multistep synthesis, exhibited fast gel times (<5 s), and rendered high ' gel-state moduli. Vat photopolymerization 3D printing afforded self-supporting organogels. Subsequent thermal treatment rendered the cross-linked PAA precursor to all-aromatic PMDA-ODA polyimide. This fast and facile strategy makes PMDA-ODA polyimides accessible in three dimensions and offers impact on aerospace or automotive technologies.
聚酰胺酸（PAA）盐适用于全芳香族聚酰亚胺的光固化增材制造工艺。由于具有全芳香族结构，这些高性能聚合物具有极高的化学和热稳定性，但传统上其酰亚胺化形式难以加工。将甲基丙烯酸2-（二甲氨基）乙酯（DMAEMA）轻松添加到市售的聚（4,4'-氧二亚苯基均苯四甲酸二胺酸）（PMDA-ODA PAA）中，可得到可紫外光固化的PAA盐溶液。这些易于制备的溶液不需要多步合成，具有快速的凝胶时间（<5秒），并具有较高的“凝胶态模量”。光固化3D打印可得到自支撑的有机凝胶。随后的热处理使交联的PAA前体转化为全芳香族PMDA-ODA聚酰亚胺。这种快速简便的策略使PMDA-ODA聚酰亚胺能够在三维空间中实现，并对航空航天或汽车技术产生影响。
