Fundamentals and Applications of Polymer Brushes in Air

Abstract

For several decades, high-density, end-tethered polymers, forming so-called polymer brushes, have inspired scientists to understand their properties and to translate them to applications. While earlier research focused on polymer brushes in liquids, it was recently recognized that these brushes can find application in air as well. In this review, we report on recent progress in unraveling fundamental concepts of brushes in air, such as their vapor-swelling and solvent partitioning. Moreover, we provide an overview of the plethora of applications in air (e.g., in sensing, separations or smart adhesives) where brushes can be key components. To conclude, we provide an outlook by identifying open questions and issues that, when solved, will pave the way for the large scale application of brushes in air.

Synthetic Route to Conjugated Donor–Acceptor Polymer Brushes via Alternating Copolymerization of Bifunctional Monomers

“…Such observation can be explained by the reduced steric hindrance during polymerization for the less-crowded growing brushes and lower chance of recombination of the neighboring chains that may significantly enhance the termination process for a high surface concentration of the initiating sites [49]. Nevertheless, further surface dilution of the initiating sites (70% grafting density) caused a significant drop of polymer thickness, likely due to a collapse of the brushes adopting mushroom or even pancake conformations [37]. Changing the grafting density has also an impact on the roughness of the obtained coatings, which, according to the AFM measurements, rises by increasing the distance between polymer chains.…”

“…Using the "grafting from" technique creates an opportunity to achieve a higher grafting density of macromolecules, as there is no steric hindrance, which can impede the process of deposition of new chains on the substrate [36]. However, the characterization of chains connected to the surface is more challenging than those dissolved previously in a solvent [37]. The surfaceinitiated polymerization approach is usually used to obtain PB, applying, among others, ATRP (atom transfer radical polymerization) [38], RAFT (reversible addition-fragmentation chain transfer polymerization) [39], NMP (nitroxide-mediated polymerization) [40], or PIMP (photoiniferter-mediated polymerization) [35] techniques.…”

Synthetic strategies to enhance the long-term stability of polymer brush coatings

“…20 Next to these bioinspired approaches, brushes can also be applied in smart adhesives, 21,22 energy devices, 23,24 bactericidal [25][26][27] and blood compatible 28,29 coatings, membranes, 30,31 nano-theranostics, 32 sensing [33][34][35] and many more applications. [36][37][38][39] End-anchored polymers can adopt different conformations. When the distance between the surface bonds is larger than two…”

“…20 Next to these bioinspired approaches, brushes can also be applied in smart adhesives, 21,22 energy devices, 23,24 bactericidal 25–27 and blood compatible 28,29 coatings, membranes, 30,31 nano-theranostics, 32 sensing 33–35 and many more applications. 36–39…”

Luminescent Surface‐Tethered Polymer Brush Materials

“…Many detailed reviews have covered the topic of surfacetethered polymers and their applications, [7,9,[39][40][41][42][43][44][45][46][47][48] however to our knowledge none have focused on surface-tethered polymers that incorporate luminescent materials. Herein, we will highlight the main approaches to prepare these materials and discuss their usage in applications such as luminescent sensors, optoelectronics, and the life sciences.…”