3D Printing All-Aromatic Polyimides Using Stereolithographic 3D Printing of Polyamic Acid Salts

Abstract

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 G′ 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.

Advances in Polyimide‐Based Materials for Space Applications

“…The same group later demonstrated AM of all‐aromatic PI employing stereolithographic AM of PAAS . In this system, 2‐(dimethylamino)ethyl methacrylate (DMAEMA) interacted electrostatically with the PAA backbone, yielding UV‐sensitive PAA DMAEMA salts.…”

Resin, cure, and polymer properties of photopolymerizable resins containing bio‐derived isosorbide

“…5,16,22,23 Numerous advances in the development of high temperature resistant and durable photopolymerizable resins were also achieved via the utility of oligomers containing both aliphatic and aromatic cores. [41][42][43] More specifically aliphatic monomers and oligomers were shown to enhance the elasticity of the resulting polymers and therefore decrease their brittleness but also their T g. 41 In contrast, aromatic monomers and oligomers rigidify the polymer backbone and lead to improved T g of the corresponding materials but make the resulting polymers more brittle. For this reason, the blends of both aliphatic and aromatic oligomers are utilized in generation of high performance materials.…”

“…Numerous advances in the development of high temperature resistant and durable photopolymerizable resins were also achieved via the utility of oligomers containing both aliphatic and aromatic cores 41–43 . More specifically aliphatic monomers and oligomers were shown to enhance the elasticity of the resulting polymers and therefore decrease their brittleness but also their T g .…”

Melt and One-Pot Solution Synthesis of Thermally Stable, Organosoluble and Photocurable Acidic Polyimides

“…Photocuring not only gives a way for the polyimide to serve as a binder polymer in typical photoresists, but also reinforces the overall thermal stability to a great extent. Polyimides which have substituents like acrylate or methacrylate, i.e., photocurable polyimides have been utilized in gate insulators for thin-film transistors [6] and 3D printing process [7] [8].…”