On the Road to Circular Polymer Brushes: Challenges and Prospects.

Polymer brushes are unique surface coatings that have been of high interest in research for the past decades due to their covalent tethering to surfaces and the broad spectrum of polymers that can be grafted to or grafted from various surfaces. Modification of surfaces with brushes may provide lubricious and/or antifouling properties, and they can also potentially be used in many application fields due to their high responsiveness toward certain stimuli. Generally, polymer brushes are long-lasting coatings, while their end-of-life has to date largely been neglected. Therefore, it is important to consider additional design methodologies to produce circular brushes, which will degrade after a certain period of time such that surfaces can be reused, and the potentially obtained monomers may be used again to synthesize new brushes. In this Perspective, we aim to tackle and understand the challenges to translate the knowledge on degradation and chemical recycling of bulk polymers toward circular polymer brushes. We summarized the recent developments on (bio)degradable polymer brushes and the challenges that are to be tackled toward their potential implementation as circular coatings.