Effect of Rolling on the Structure of Fibrous Materials Based on Poly(3-Hydroxybutyrate) and Obtained by Electrospinning

In this paper, we study the effect of rolling on the structure of fibrous materials based on poly(3-hydroxybutyrate) (PHB) and obtained by electrospinning. We have used electron paramagnetic resonance to demonstrate the effect of water and an oxidant (ozone) on the amorphous phase of the PHB matrix, formed by ultrathin fibers. We have established that additional orientation of PHB spherulites in a mechanical field leads to stabilization of the amorphous regions, which are more resistant to exposure to an aggressive ozone atmosphere. Studying the DSC curves for melting of the fibrous materials has shown that mechanical rolling leads to a bimodal distribution of the crystalline phase into more perfect and less perfect crystalline regions. The series of studies of ultrathin fibers proposed made it possible to analyze the changes in the segmental mobility of the polymer molecules in the early stages of their interaction with aqueous and oxidizing aggressive environments.