Phase Transitions in Poly(Vinylidene Fluoride)-Based Composite under Mechanical Stresses

Abstract

The phase transition in composites based on polyvinylidene fluoride and cobalt ferrite nanoparticles under uniaxial stretching at 100, 200, and 300% has been investigated. It was found that, when the composite is stretched at 300%, there is a maximum increase in the β-phase fraction: from 1% for the unstretched sample to 91%, while the fraction of the electrically active phase increases from 74 to 92%. It was also established that tensile stretching of the composites leads to an increase in the tensile strength: from 5.7 to 85.0 MPa. This tensile pattern also contributes to the increase in coercivity, which is due to the increase in the interparticle distance in the composite structure. These results emphasize the importance of the mechanical properties and phase changes in ferrite-containing polymer composites for their future applications.