Synchronized polymerization and fabrication of poly(acrylic acid) and nylon hybrid mats in electrospinning

Acrylic acid monomer in a viscous supporting nylon solution was polymerized and fabricated simultaneously via an electrospinning process. This novel polymerization method defines the fiber morphology as a network of interconnected mats. This network consists of smaller poly(acrylic acid) (PAA) fibers, approximately 19 nm in diameter, and larger nylon 6 fibers, approximately 75 nm in diameter. These two different fibers are separated by extraction of PAA from the fibrous mat in water and differentiation of field-emission scanning electron microscopy (FESEM) images of the same mat using before and after extraction of PAA. The structure of the extracted PAA was confirmed by ¹H NMR and Fourier transform infrared (FT-IR) analysis. The observed modification to conventional electrospun mats is due to the presence of an extra phase-separated PAA produced by the electrospinning polymerization process. Finally, fiber morphologies and hybrid property were characterized via FT-IR, FESEM, thermogravimetric analysis, and X-ray diffraction. Similarly extracted samples and synthesis PAA were characterized in FT-IR and ¹H NMR spectroscopy.