Radiation Functionalisation of Thermal and Mechanical Properties of Polyethylene Composites with Multi-Walled Carbon Nanotube

This study investigates radiation-functionalised low-density polyethylene (LDPE) nanocomposites containing multi-walled carbon nanotubes (MWCNTs) at absorbed doses ranging from 0.1 to 4.72 MGy. The thermophysical and mechanical properties, as well as the Raman spectra, of these composites were studied. An increase in the absorbed dose of electron irradiation, from 0.05 to 4.72 MGy, resulted in complex transformations of the intramolecular structure, due to the mechanochemical effect of macrochain destruction and cross-linking in crystalline and amorphous regions. Quantum chemical calculations were performed to optimise the geometry, infrared absorption spectra, combinational scattering, charge distribution, molecular orbital shapes, and localisation of energy levels within the electron forbidden zone. The electron transition configurations for the PE chain (C ₉ H ₂₀ ) were also optimised. It was established that the C ₉ H ₂₀ molecule is linear with a trans conformation. Single bonds between carbon and hydrogen atoms form σ-type molecular orbitals. The frequencies of the calculated vibrational spectra best agree in the range of deformation vibrations.