Preparation of poly(methyl methacrylate) fibers via electrospinning in different solvent and its morphology comparison

Abstract

In this study, poly(methyl methacrylate) PMMA was synthesized and electrospun into fibers in different solvents. Synthesis of PMMA was done by free radical polymerization (FRP). Benzoyl peroxide (BPO) acts as an initiator and methyl methacrylate (MMA) as a monomer. The reaction was done in tetrahydrofuran (THF) solvent at polymerization temperature 80 °C for 24 hours. Spectroscopic methods of ¹H NMR and ATR were used to confirm the conversion and the structure of the synthesized polymer. Both synthesized and commercial PMMA is used to study the effect of solvent system and viscosity of polymer in electrospinning technique. Four different solvents, chloroform, dichloromethane (DCM), dimethyl sulfoxide (DMSO) and a binary solvent (1:1 ratio of chloroform and DCM) were studied. The parameters for the electrospinning such as concentration of polymer (0.2 g/ml), voltage (20 kV), volume of polymer (10 ml), flow rate (1.2 ml/h) and tip to collector distance (15 cm) are kept constant throughout the experiment. The PMMA was electrospun horizontally for approximately 8 hours. The morphology of PMMA fibers obtained were analyzed by using SEM. Beaded fibers are generated when PMMA in DCM and chloroform solution respectively. Commercial PMMA in binary solvent afforded more fibers with a few of beads while synthesized PMMA produced a lot of beads. However, electrospinning of PMMA in DMSO solvent cannot be done due to the highly dielectric constant of DMSO. Thus, this showed that the solvent system has an effect on the morphology of the fibers due to its boiling point and dielectric constant properties.