| Abstract [eng] |
Due to their unique and easily adjustable properties, functional materials, including composites and metastructures, find numerous applications in modern engineering. The current work is devoted to the experimental investigation of functional materials for application in gigahertz and terahertz frequency ranges including the creation of composite materials with nanocarbon fillers and broadband characterization of their electromagnetic properties and the development of novel material engineering techniques in order to produce the structures with predictable and controllable electromagnetic properties in desired frequency ranges. In this work, the terahertz spectroscopy was applied as a non-invasive method of the filler distribution control in polymer composites. The presence of insulated nanocarbon inclusions in composites both below and above the percolation threshold was indicated by a maximum of the imaginary part of a composite’s permittivity. The significant absorption of microwave and THz radiation was achieved in tridimensional periodic structures that were created through the selective laser sintering of polyurethane/nanocarbon segregated media, due to their multi-level porosity. Finally, a novel technique of material engineering based on the combination of laser profiling followed by polymer impregnation of vertically aligned multi-walled carbon nanotubes arrays was introduced. |
