Partial Disentanglement in Continuous Polystyrene Electrospun Fibers

Electrospun fibers show a rich and complex variety of diameter-dependent properties. Chain orientation, confinement, and partial disentanglement are the three main factors that have been proposed to explain these phenomena. While molecular orientation is currently the subject of intensive study, the others are more challenging to probe experimentally. Here, we provide support for partial disentanglement in continuous polystyrene electrospun fibers on the basis of infrared spectroscopy measurements. We show that the fiber’s capability to remain partially disentangled, and ours to detect it, is highly dependent on the initial polymer concentration and on the time the fibers are allowed to accumulate on the collector. A model, based on the core–shell morphology observed for the fibers, is proposed to explain the experimental observations