Impact of ultraviolet radiation on graphene structure and PnBMA-graphene antistatic coating

The influence of prolonged ultraviolet (UV) irradiation on the structural and functional properties of graphene deposited on copper, silicon, and poly(butyl methacrylate) (PnBMA) substrates has been investigated. Using Raman spectroscopy, it was shown that UV exposure induces various types of defects, the nature of which is determined by both the substrate type and the number of graphene layers. It was established that for the transferred PnBMA/Gr1 and PnBMA/Gr2 coatings, a significant increase in specific surface resistance is observed after irradiation, with more pronounced degradation of conductivity being characteristic of the PnBMA/Gr2 sample with fewer graphene layers. It is important to note that despite the increase in resistance, its values for all studied "graphene-PnBMA" coatings remained within the antistatic range (10 4 –10 12 Ω/sq) throughout the experiment. The incorporation of commercial graphene nanoparticles into the PnBMA matrix (NP-Gr/PBMA) significantly enhances stability: the composite maintained antistatic properties (resistance of 2–3 kΩ/sq) even after 168 h of irradiation. A critical effect of UV exposure is the transition of the coating surfaces from a hydrophobic to a hydrophilic state due to the photo-oxidation of graphene, which was particularly pronounced in the PnBMA/Gr1 sample. The results demonstrate that the stability of graphene-containing coatings under UV irradiation is determined by the number of graphene layers and the properties of the substrate.