Unveiling\nAqueous Polymerization of Poly(amic acid)\nSalts for Eco-Friendly and Robust Aromatic Polyimide Structuring

The development of water-borne poly(amic acid) salts\n(W-PAAS) for\naromatic polyimide (PI) synthesis represents a significant advancement,\noffering a straightforward and environmentally friendly process. This\nstudy provides an in-depth investigation into the intricate reaction\nmechanisms of W-PAAS polymerization in an aqueous medium facilitated\nby an organic base. The polymerization primarily occurs at the interface\nof dianhydride particles with water, highlighting the critical role\nof this interface in the reaction. The presence of the organic base\nlowers the energy barrier, enabling the formation of high-molecular-weight\npolymer chains. The resulting PI films derived from W-PAAS aqueous\nsolutions exhibit properties comparable to those of traditional organic-solvent-based\nand commercial PI films. Additionally, the W-PAAS solution can be\neasily transformed into a hydrogel, highlighting its potential for\nthree-dimensional (3D) structuring applications. This research introduces\na novel platform for rational molecular design within aqueous synthetic\nsystems, broadening the scope of high-performance material applications\nwhile promoting environmental sustainability.