Effect of Cellulose Acetate on the Physicochemical Properties of PVP Blended Nanofibers

Background: Electrospun polymeric nanofibers are increasingly utilized in various fields due to their cost-effective production and diverse applications. Polyvinylpyrrolidone (PVP) is a pop-ular choice for nanofiber production due to its biocompatibility and favorable mechanical properties. However, its high solubility and bead formation limit its application. Objective: This study aims to investigate the effect of blending cellulose acetate (CA) with PVP to improve the physicochemical properties of electrospun nanofibers, specifically targeting diameter re-duction and minimization of bead formation. Methods: Precursor solutions of 40 wt% PVP and 12.5 wt% CA were prepared and blended in ratios of 100:0, 90:10, and 70:30 (w/w). Electrospinning was conducted at an optimized voltage of 18 kV and a flow rate of 0.050 mm/min. The resulting nanofibers were characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). method: Experimental procedures The precursor solution was made first by dissolving each PVP and CA in 98% glacial acetic acid. The solutions of PVP and CA were made at concentrations of 40 wt% and 12.5 wt%, respectively. The CA solution was then mixed with PVP solution in three different ratios (100:0; 90:10; and 70:30 PVP/CA, respectively). The mixed solutions were stirred at ambient temperature until they became fully homogeneous. The prepared composite solutions were then electrospun to produce composite fibers. The polymer solution was placed in a 10 mL plastic syringe fitted with a stainless-steel needle of 1.20 x 38 mm tip dimensions. A high-voltage power supply was used to produce the voltages ranging from 12 to 25 kV and the distance between the nozzle and the collector screen was kept at 10 cm. A syringe pump was used to feed the polymer solution into the needle tip at a 0.050 mm/min rate. Characterization: The morphology of the prepared electrospun nanofibers was observed under scanning electron microscopy (SEM: FEI-QUANTA 200F, Netherlands) at an accelerating voltage of 15 kV. The average diameter of the fibers was determined using Origin ver.8.5 software (OriginLab Corporation, USA). The chemical composition of the prepared samples was studied by Fourier transform infrared spectroscopy, using a Spectrum PerkinElmer (Wiesbaden, Germany) at a wavelength range of 4,000 – 650 cm−1. Results: The PVP and CA blending ratios, 100:0, 90:10, and 70:30, gave fibers with average diameters of 460 nm, 327 nm, and 281 nm based on the SEM images. Discussion: Blending CA with PVP reduced fiber diameter and bead formation. SEM revealed a de-creasing trend in the average diameters with increasing loading of the CA polymer. FTIR spectra showed characteristic peak shifts, indicating hydrogen bonding between the two polymers. Conclusion: The addition of CA significantly improved the morphology and physicochemical prop-erties of PVP nanofibers. Optimal results were achieved at an 18 kV voltage and a 70:30 PVP/CA blend, yielding smooth, bead-free nanofibers with enhanced structural integrity.