In this communication, surface-initiated photoinduced electron transfer-reversible addition–fragmentation chain transfer polymerization (SI-PET-RAFT) is introduced. SI-PET-RAFT affords functionalization of surfaces with spatiotemporal control and provides oxygen tolerance under ambient conditions. All hallmarks of controlled radical polymerization (CRP) are met, affording well-defined polymerization kinetics, and chain end retention to allow subsequent extension of active chain ends to form block copolymers. The modularity and versatility of SI-PET-RAFT is highlighted through significant flexibility with respect to the choice of monomer, light source and wavelength, and photoredox catalyst. The ability to obtain complex patterns in the presence of air is a significant contribution to help pave the way for CRP-based surface functionalization into commercial application.

Hydrophilic surface coatings have made it into commercial application as possible solutions for problems such as fogging, frosting, and biofouling. However, there is an inherent contradiction: superhydrophilic coatings can prevent these unwanted phenomena, but they are also readily dissolved by water. To address this longevity concern, the present work introduces a fully aqueous surface-initiated (SI) polymerization under ambient conditions for the facile formation of durable superhydrophilic polymer coatings. The aqueous SI photoinduced electron transfer reversible addition−fragmentation chain transfer polymerization (SI-PET-RAFT) approach developed herein uses water as a sole solvent and can be performed in an ambient air atmosphere. This circumvents traditional shortcomings in SI radical polymerization related to limited hydrophilic monomer solubility in organic solvents and oxygen tolerance. In addition, polymerization under mild yellow light eliminates possible substrate degradation that can occur with conventional thermal or UV-light treatment. The cationic, anionic, and zwitterionic polymer films engineered in this study show promise as functional materials with enhanced durability, demonstrated to effectively combat the challenge of surface fogging. The described approach is user-friendly, cost-and time-efficient, and scalable and produces efficient anti-fogging coatings that outperform commercial solutions in both optical quality and durability.

Surface‐tethered macromolecules, or polymer brushes, offer a unique platform for coating surfaces for a wide variety of applications. Surface‐initiated polymerization (SI‐P), through which polymer brushes can be grown directly from an initiator‐functionalized surface, offers a facile, highly customizable approach that is synergistic with photolithography. Using a variety of photolithography devices and SI‐Ps, complex polymer brush architectures can be fabricated with great spatial and temporal control. This article not only addresses techniques, advancements, applications, and possible future directions within the field of polymer brush photolithography, but it also provides resources to assist the reader in selecting the polymerization technique and photolithography device most conducive to a given endeavor.

Over the past three decades, the development of reversible deactivation radical polymerizations (RDRP), and advancements toward more user-friendly and accessible experimental setups have opened the door for nonexperts to design complex macromolecules with well-defined properties. External mediation, improved tolerance to oxygen, and increased reaction volumes for higher synthetic output are some of the many noteworthy technical improvements. The development of RDRPs in solution was paralleled by their application on solid substrates to synthesize surface-grafted “polymer brushes” via surface-initiated RDRP (SI-RDRP). This Viewpoint paper provides a current perspective on recent developments in SI-RDRP methods that are tolerant to oxygen, especially highlighting those that could potentially enable scaling up of the synthesis of brushes for the functionalization of technologically relevant materials.

Photocatalysis is a valuable and versatile method to perform a variety of chemical transformations under ambient temperatures and pressures using mild visible light. This work showcases an example of fluorescein-functionalized polymers grafted to micro-scale glass beads as heterogeneous photoredox catalysts. X-ray photoelectron spectroscopy and thermogravimetric analysis were used to analyze the resulting functional glass beads. Model reactions that are demonstrated include a cyclic condensation and a radical dehalogenation that can both be performed to high yields. Successful recyclability of the fluorescein polymer brush beads is demonstrated with detailed characterization confirming that photocatalytic polymer brushes remain tethered to the surface. As such, this allows for purification and reuse of the heterogeneous photocatalyst beads after simple filtration.

An oxygen-tolerant approach is described for preparing surface-tethered polymer films of organic semiconductors directly from electrode substrates using polymer brush photolithography.Aphotoinduced electron transferreversible addition-fragmentation chain transfer (PET-RAFT) approach was used to prepare multiblockp olymer architectures with the structures of multi-layer organic light-emitting diodes (OLEDs), including electron-transport, emissive,a nd hole-transport layers.T he preparation of thermally activated delayed fluorescence (TADF) and thermally assisted fluorescence (TAF) trilayer OLED architectures are described. By using direct photomasking as well as ad igital micromirror device,wealso showthat the surface-initiated (SI)-PET-RAFT approach allows for enhanced control over layer thickness,and spatial resolution in polymer brush patterning at lowc ost.

The reproducibility of polymer brush synthesis via surface‐initiated controlled radical polymerization is interrogated. Experiments compare the stability of initiating monolayers for surface‐initiated (SI) reversible addition‐fragmentation chain transfer polymerization (SI‐RAFT) and SI atom transfer radical polymerization (SI‐ATRP). Initiator‐functionalized substrates are stored under various conditions and grafting densities of the resulting polymer brush films are determined via in situ ellipsometry. Decomposition of one of the examined SI‐RAFT initiators results in limited reproducibility for polymer brush surface modification. In contrast, initiators for SI‐ATRP show excellent stability and reproducibility. While both techniques bring inherent benefits and limitations, the described findings will help scientists choose the most efficient technique for their goals in chemical and topographical surface modification.

Polycarbonate (PC) is a popular consumer plastic due to its light weight, optical clarity, mechanical strength, and temperature stability. Though nontoxic and biocompatible, its inherent hydrophobicity limits its potential in applications that require hydrophilicity or use in the body. This work presents a facile method to chemically modify PC surfaces with superhydrophilic polymer brushes. A method is developed to immobilize reversible addition−fragmentation chain transfer (RAFT) agents on PC substrates. From these PC-tethered RAFT initiators, hydrophilic polymer brushes are grown under aqueous conditions, visible light, and ambient atmosphere. The resulting films decrease PC surface water contact angles (θ) to as low as θ < 10°(superhydrophilic) by continuous growth or sequential extension. This work expands the realm of possibility for uses of PC from anti-fogging lenses to durable biological devices, allowing scientists and engineers to take advantage of the many attractive physical properties of PC without limitations of hydrophobicity.