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Sustainable carbon dots comprising surficial oxime ester groups following homolytic bond cleavage exhibit potential as photoinitiators for traditional free radical photopolymerization. Carbon dots were made following a solvothermal procedure from sustainable furfural available from lignocellulose. Surficial aldehyde moieties reacted with hydroxylamine to the respective oxime while reaction with benzoyl chloride resulted in a biobased Type I photoinitiator comprising sustainable carbon dot (CD‐PI). Photoinitiating ability was compared with the traditional photoinitiator (PI) ethyl (2,4,6‐trimethyl benzoyl) phenyl phosphinate (TPO‐L) by real‐time FTIR with UV exposure at 365 nm. Photopolymer composition based on a mixture of urethane dimethacrylate (UDMA) and tripropylene glycol diacrylate (TPGDA) resulted in a similar final conversion of about 70 % using either CD‐PI or TPO‐L. Nevertheless, it appeared homogeneous in the case of compositions processed with CD‐PI, while those made with TPO‐L were heterogeneous as shown by two glass transition temperatures. Moreover, the migration rate of CD‐PI in the cured samples was lower in comparison with those samples using TPO‐L as PI. [ABSTRACT FROM AUTHOR]

A sustainable photocatalyst for use with multiple purpose comprising demethylated lignin (Fe3O4@D‐wood) was made by treatment of wood and iron oxide. Characterization followed by XRD, UV/Vis, photo‐current studies, and electrochemical measurements. This material became subject of photocatalytic explorations for water treatment and material synthesis by radical photopolymerization. Exposure of Fe3O4@D‐wood with artificial sunlight showed an improved activity considering photochemical oxidation of organic pollutants in the presence of H2O2. The efficient generation of reactive radicals brought this system also to photopolymerization. Here, radicals based on reactive oxygen species (ROS) generated in the catalytic cycle can be seen as the dominating species to initiate radical polymerization. A mixture of UDMA and TPGDA showed good reactivity with cumene hydroperoxide (CHP). Photocatalyst used for water treatment facilitates reuse for photopolymerization. [ABSTRACT FROM AUTHOR]