A Facile Visible‐Light‐Induced Route to Functionalize Polymeric Substrates by Combining Controlled Radical Grafting Polymerization and Thiol−Yne Click Chemistry with Photoredox Catalyst Ir(ppy)₃

Abstract

A novel strategy, based on surface‐initiated grafting polymerization and post‐polymerization thiol‐yne click chemistry, with Ir(ppy)3 as a sole photoredox catalyst, under visible light irradiation is developed. The “livingness” of the grafting polymerization is demonstrated by the linear increase of the graft yield with irradiation time and the block grafting polymerization. Then, acetenyl groups of poly(propargyl methacrylate) (PPMA) grafting chains are reacted with pentaerythritoltetra‐(3‐mercaptopropionate) via the thiol‐yne click reaction. The successful introduction of reactive thiol groups onto the low‐density polyethylene‐graft‐poly(propargyl methacrylate) (LDPE‐g‐PPMA) films is demonstrated by Fourier transform IR (FTIR) and X‐ray photoelectron spectra (XPS) spectroscopy, and the thiol‐ene click reaction with N‐(1‐pyrenyl) maleimide.

Iron complexes as potential photocatalysts for controlled radical photopolymerizations: A tool for modifications and patterning of surfaces

“…These last decades, controlled/living radical polymerization (CRP) has been the subject of intense efforts and great attention . More recently, the use of light in CRP has been introduced . The controlled radical photopolymerization (CRP2) benefits of different advantages compared with CRP, including a spatial and temporal control of the polymerization reaction but also the possibility to carry out the polymer synthesis at room temperature to avoid undesired side reactions.…”

“…Albeit the photoiniferter and the nitroxide‐mediated photopolymerization were developed, and the use of organometallic complexes as photocatalysts (PC) to control the polymerization processes has been elegantly proposed . The use of pure organic molecules as photocatalyts has also been elegantly developed in recent years .…”

“…The use of pure organic molecules as photocatalyts has also been elegantly developed in recent years . Therefore, several families of PCs have been checked for the generation of radicals usable in polymerization reactions under very soft conditions and their ability to operate in CRP2, among them the copper, iridium, ruthenium complex series, or organic molecules . The reaction mechanisms are usually described by photoredox catalytic cycles through a process originally called the “photoredox catalysis” in organic synthesis …”

Synthesis, Characterization, and Ion Sensing Application of Pyrene‐Containing Chemical Probes

“…Pyrene‐containing macromolecular structures have attracted a great deal of attention to be employed in fluorescent probes due to their long fluorescence lifetime and a well‐defined fluorescence spectrum, which is sensitive to the polarity of the environment . There are numerous studies in the literature on the fluorescence sensor applications of pyrene‐containing molecular compounds and high‐molecular polymers toward various analytes, including nitroaromatic compounds, metal ions, anions, and glucose …”

Visible light-induced controlled radical polymerization of methacrylates with perfluoroalkyl iodide as the initiator in conjugation with a photoredox catalyst fac -[Ir(ppy)]3

“…Very recently, a novel strategy, based on surface‐initiated grafting polymerization and post polymerization thiol‐yne click chemistry, with Ir III as the sole photoredox catalyst and under visible light irradiation has been developed to functionalize the polymeric film substrate. At first, the visible light‐mediated surface‐initiated grafting polymerization of poly(propargyl methacrylate) was carried out after which the grafting chains were reacted with pentaerythritoltetra‐(3‐mercaptopropionate) via thiol‐yne click reaction to introduce reactive thiol groups onto LDPE films …”