Parameters’ Influence on Electrospun Polystyrene-Grubbs’ Catalyst Composite Fibers Morphology

Abstract

Electrospinning represents a simple, cost-effective technique that allows the production of continuous fibers, with diameters ranging from the micrometer to the nanometer scale. Mixing particles in the polymer feed solution could result in composite fibers, with various potential applications, depending on the particle filler. The influence of electrospinning parameters on the fiber morphology must be investigated to obtain undamaged fibers without large agglomerates. This research presents polystyrene (PS)-based electrospun composite fibers, containing the first- and the second-generation Grubbs’ catalyst (G1 and G2). Loading of both catalysts was 1[Formula: see text]wt.% in the composite fibers, and the influence of different solution flow rates on fiber diameter, shape and regularity was investigated. Applied flow rates were 5, 10, 15 and 20[Formula: see text]ml/h for both composites (PS-G1 and PS-G2). Software analysis of field emission scanning electron microscopy (FESEM) images has revealed that flow rate has a higher influence on the diameter increase in PS-G1 compared to PS-G2, due to a difference in electrostatic forces and polymer-catalyst interactions. In both composites, 10[Formula: see text]ml/h was the threshold for producing smooth and undamaged fibers, further enhanced in PS-G2, where large agglomerates were observed at 20[Formula: see text]ml/h. Furthermore, in both composites, fiber diameter distribution was significantly wider at higher flow rates, which is not a desirable feature in composites. The presented results demonstrated the synergy between different parameters that influence the formation and morphology of electrospun PS-based composites and could help in the future design and processing of continuous composite fibers.