Fabrication of Complex Three‐Dimensional Polymer Brush Nanostructures through Light‐Mediated Living Radical Polymerization

Abstract

Ein einfacher Zugang zu gemusterten 3D‐Polymerbürsten basiert auf einer durch sichtbares Licht angeregten radikalischen Polymerisation. Die zeitliche und örtliche Kontrolle der Polymerisation ermöglicht die Musterung der Polymerbürsten ausgehend von einer einheitlichen Initiatorschicht durch eine einfache Photomaske (siehe Bild). Durch Änderung der Lichtintensität können unter anderem gemusterte Polymerblöcke und komplexe 3D‐Strukturen aufgebaut werden.

Photomediated controlled radical polymerization

“…In the Mn-mediated photoATRP processes Mn 2 (CO) 10 was used to graft Ir-mediated photoATRP of MMA from silicon substrates carrying a self-assembled monolayer (SAM) of BiB-based was successful, Figure 39. [317]. The substrates were covered with a thin glass slide to ensure short path lengths of the employed visible light.…”

“…MMA, OEGMA and various fluorinated methacrylates were polymerized and yielded film thicknesses between 60 and 120 nm within a one hour brush polymerization time. [317,318] Ionic monomers such as 2methacryloyloxyethyl phosphorylcholine and sulfobetaine methacrylate formed only very thin layers, even with trifluoroethanol as co-solvent. [318] Catalyst concentrations were kept at 50 ppm for MMA, [317] but were increased to 500 ppm for OEGMA and fluorinated monomers.…”

Hydrogel Pore‐Size Modulation for Enhanced Single‐Cell Western Blotting

“…A grayscale photomask spatially attenuates UV intensity, [23] thus locally altering the rate of free-radical production and polymerization. [24] If polymerization is halted prior to completion, the grayscale mask opacity determines the local effective gel density.…”

Visible‐Light‐Induced Controlled Polymerization of Hydrophilic Monomers with Ir(ppy)3 as a Photoredox Catalyst in Anisole

“…Then, the excited Ir III* complex reacts with P n ‐Br to generate the desired radical and Ir IV Br complex, which can reacts with the propagating radical to regenerate Ir III and the dormant species. In the following studies, the fac ‐[Ir(ppy) 3 ]‐catalyzed CRP was extended to the surface‐initiated grafting polymerization on silica substrates . This technology has been also successfully applied to prepare block copolymers.…”