Polymer composite materials that combine magnetic and electrical properties are the subjects of particular attention for modern-day researchers. Their basic property is the ability to convert electric polarization into a magnetic field and vice versa. Although some materials exhibit a much better magnetoelectric effect, polymer-based composites are easier not only to produce but also to modify.
Such composites have great potential in a variety of different fields. For example, using them as a basis, scientists can develop surfaces that help cultivate various cells. In this case, polymer composites serve as a substrate through which it is possible to affect the culture using a non-contact and controlled electric charge and morphological properties of the surface. It allows simulating natural conditions in the body. Due to such ample opportunities, researchers have been trying to improve the efficiency of the material for several years.
With the help of Russian and foreign colleagues, scientists from the I. Kant Baltic Federal University created two types of composites based on poly(vinylidene fluoride) (PVDF) polymers and a PVDF-based copolymer with the use of PVDF-TrFE trifluoroethylene.
Poly(vinylidene fluoride) is a multipurpose material with a wide array of applications. In a certain crystalline phase, it possesses piezoelectric properties that are expressed in the emergence of electrical polarization under the mechanical influence. Composites developed by the researchers demonstrate a change in polarization both under mechanical impact and the influence of a magnetic field due to the inclusion of magnetic nanoparticles in the polymer structure.
The researchers followed various approaches to modify nanocomposites in order to amplify and control the magnetoelectric response. They used a PVDF-based copolymer with extra pronounced piezoelectric properties, then tried additives from piezoelectric and magnetic particles. The results of the experiments show that the addition of particles of barium titanate (BaTiO3) with a concentration of 5-10% can significantly enhance the magneto-electric effect.
"We have also shown that our composites are biocompatible, that is, they do not harm living systems. This was confirmed in our experiment with the embryonic stem cells of mice. This type of cell is very sensitive to the conditions of cultivation, including the properties of the substrate. Further research will be aimed at increasing the magnetoelectric effect. This is possible due to changes in the size, shape, and concentration of particles in such composites", Kateryna Levada comments, Ph.D., the Head of the Biomedical Applications Laboratory of the REC "Smart Materials and Biomedical Applications".