Synthesis of Water-Soluble Salts of Poly(amic acids) and Structural Features of Fibers and Films Obtained on Their Basis

Three water-soluble salts of poly[(4.4'-oxydiphenylene)pyromellitamic acid] with different chemical structure are synthesized. The data on their stability over time, rheological properties of aqueous solutions, density, and surface tension necessary for electrospinning are presented. Using scanning electron and atomic force microscopy, the structural-morphological characteristics of the synthesized water-soluble salts of poly(amic acids) and submicron fibers formed during electrospinning are studied. On the basis of water-soluble ammonia and triethylammonium salts of poly[(4,4'-oxydiphenylene)pyromellitamic acid] fibrous nonwoven materials are obtained for the first time. For the nonwoven material based on triethylammonium salt, physical and mechanical properties are determined.