Light Modulation in Magnetic Polymer Composite Nanofibrous Membranes by Applying a Variable Magnetic Field

Polymeric composites have attracted interest from researchers due to their physical properties that can be modified by adding different kinds of filler. Among the different types of composite materials, the magnetic polymeric composite nanofibers have shown interesting properties attributable to their size and morphology where the magneto-optical and magnetostrictive effects can be exploited to design sensors and actuators. This article focuses on the fabrication and characterization of two kinds of magnetic electrospun membranes and their application as light modulators by the effect of the magnetic field. The first membrane is based on the polylactic acid (PLA) mixed with cobalt ferrite (CoFe
₂
O
₄
), and the second membrane is based on the PLA with magnetite particles (PLA-Fe
₃
O
₄
) and polyvinylidene fluoride (PVDF); in this membrane, the PVDF was added to improve the brittleness of PLA. The morphological analysis of the PLA/CoFe
₂
O
₄
and PLA-Fe
₃
O
₄
/PVDF samples was performed by scanning electron microscopy (SEM). The light modulation effect of the magnetic membranes was tested by applying a variable magnetic field and measuring the radiant flux (irradiance) of a laser light through the membrane. In addition, PLA/CoFe
₂
O
₄
and PLA-Fe
₃
O
₄
/PVDF films were fabricated and tested to understand the mechanisms involved in the light modulation of the proposed membranes. The results indicate that the applied magnetic field changed the optical properties and the porous structure of the membranes, resulting in the change in the transmission of the light through the membranes.