20.500.12556/DiRROS-17214 Evolution of surface functional groups and aromatic ring degradation upon treatment of polystyrene with hydroxyl radicals The surface properties of hydrocarbon polymers are inadequate for numerous applications. Hence, they require alteration via functionalisation with desired functional groups. Hydroxyl groups are often preferred, since they enable appropriate polarity for the irreversible grafting of desired molecules. In this study, the surface kinetics resulting from the treatment of polystyrene with hydroxyl (OH) radicals from the gas phase was fundamentally investigated through a precisely-designed experiment. Polystyrene samples were exposed to various known fluences of OH radicals, and the evolution of surface functional groups versus the OH fluence was monitored using high-resolution X-ray photoelectron spectroscopy (XPS). The fluences of OH radicals varied between 1 × 1018 and 4 × 1023 m−2 in the process of finding a threshold fluence for the formation of specific groups. The surface concentration of carbonyl (C=O) groups could be measured using XPS at a fluence of approximately 5 × 1020 m−2. The C=O groups became measurable at a fluence of approximately 1.5 × 1021 m−2, and carboxyl (COOH)/ester groups at approximately 4 × 1021 m−2. As deduced from the XPS, a concentration of C=O groups at approximately 5 % occurred before the degradation of the aromatic ring. The formation of other oxygen-functional groups required opening of the aromatic ring. The results have been explained using a two-step process, considering available theories vis-a-vis initial stages in the functionalisation of PS with polar functional groups. polistiren kinetika površinske funkcionalizacije OH radikali vpliv doze radikalov časovni razvoj polystyrene surface functionalisation kinetics OH radicals true false false Elsevier Nizozemska Angleški jezik Ni določen Neznano 2023-11-09 08:19:53 2023-11-09 08:19:54 2023-11-10 03:35:07 0000-00-00 00:00:00 2023 0 0 Opis vira z dne 2. 11. 2023; Nasl. z nasl. zaslona; str. 1-9 Vol. 218 Dec. 2023 0000-00-00 PostprintKoncna Objavljeno NiDoloceno 2023-08-19 2023-10-24 2023-10-27 2025-10-27 620.1/.2 1873-2321 doi.org/10.1016/j.polymdegradstab.2023.110582 170551299 https://www.sciencedirect.com/science/article/abs/pii/S0141391023003312 1 ffe45cf2-7ec7-11ee-9ccb-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=23383 RAZ_Vesel_Alenka_2023.docx RAZ_Vesel_Alenka_2023.docx 1 2E7FA72A464B75356E6C1109BC8F191E a6fe1555f4d471135407d6c354fbd2eb8956fe5573423b036a30c63035f3c435 e9d2d058-7ec9-11ee-9ccb-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=23384 Institut Jožef Stefan 0 0 0