This article aims to merge two evolving technologies, namely additive manufacturing and composite manufacturing, to achieve the production of high-quality and low-cost composite structures utilizing additive manufacturing molding technology. This work studied additive manufacturing processing parameters at various processing stages on final printed part performance, specifically how altering featured wall thickness and layer height combine to affect final porosity. Results showed that reducing the layer height yielded a 90% improvement in pristine porosity reduction. Optimal processing parameters were combined and utilized to design and print a closed additive manufacturing molding tool to demonstrate flexible composite manufacturing by fabricating a composite laminate. Non-destructive and destructive methods were used to analyze the composite structures. Compared to the well-established composite manufacturing processes of hand lay-up and vacuum-assisted resin transfer molding methods, additive manufacturing molding composites were shown to have comparable material strength properties.

This study introduces a novel polyimide vitrimer ink specifically formulated for additive manufacturing on non-planar textile surface (i.e., Kevlar) substrates, aiming to advance the integration of strain sensors in aerospace and defense applications. The ink incorporates disulfide exchanges that enable reversible covalent adaptability, facilitating post-processing modifications and enhancing material recyclability. The synthesis involved a two-step process under nitrogen atmosphere, starting with the formation of polyamic acid (PAA) from 4-amino phenyl disulfide and pyromellitic dianhydride, followed by making the polymer UV-sensitive through the addition of a DMAEMA salt solution and a photoinitiator. Optimal printing parameters were established through experimental tuning of viscosity and modulus, enabling effective direct ink writing (DIW) on Kevlar. The printed sensors exhibited high sensitivity and durability under mechanical stress. Notably, the vitrimer’s disulfide linkages allowed for straightforward removal from substrates using a tailored solvent mixture, underscoring the potential for reusability and recycling in practical applications. This research demonstrates that polyimide vitrimers can be effectively used to create high-performance, adaptable, and recyclable sensors via additive manufacturing, providing a significant advancement in the field of smart materials for dynamic and harsh environments.