Self‐Healable Hydrophobic Material Based on Anthracenyl Functionalized Fluorous Block Copolymers via Reversible Addition‐Fragmentation Chain Transfer Polymerization and Rapid Diels–Alder Reaction

• Published in: Macromolecular materials and engineering Vol. 306; no. 10
• Main Authors: Ponnupandian, Siva, Mondal, Prantik, Lowe, Andrew B., Singha, Nikhil K.
• Format: Journal Article
• Language: English
• Published: Weinheim John Wiley & Sons, Inc 01.10.2021
• Subjects: 1,2,4‐triazoline‐3,5‐dione chemistry; Addition polymerization; Block copolymers; Chain transfer; Chains (polymeric); Conjugates; Contact angle; Diels-Alder reactions; Diels–Alder reaction; Differential scanning calorimetry; Diketones; Esterification; Fluoropolymers; Fragmentation; Healing; hydrophobic polymers; Hydrophobicity; Hydroxyl groups; Paints; Polyhydroxyethyl methacrylate; Polymerization; Polymers; rapid polymerization; reversible addition‐fragmentation chain transfer; Room temperature; self‐healing
• ISSN: 1438-7492; 1439-2054
• DOI: 10.1002/mame.202100307

Recently, among the available approaches to develop self‐healable materials, 1,2,4‐triazoline‐3,5‐dione (TAD)‐based Diels–Alder (DA) chemistry has gained tremendous attention, becuase this DA reaction is very rapid under ambient conditions. This study delineates developing a self‐healing hydrophobic fluorinated polymer utilizing dynamic and rapid TAD‐DA chemistry. For this purpose, block copolymers of 2‐hydroxyethyl methacrylate (HEMA) and 2,2,2‐trifluoroethylmethacrylate (TFEMA) are prepared via reversible addition‐fragmentation chain transfer polymerization. Subsequently, the pendant hydroxyl groups of the HEMA repeat units are modified with anthracenyl functionality via esterification with 9‐anthracenecarboxylic acid. The tailor‐made polymer‐bearing anthracenyl pendants are subsequently crosslinked via a rapid DA reaction using a bifunctional TAD derivative at room temperature (r.t.). Differential scanning calorimetry (DSC) analysis is performed to interpret the thermoreversible behavior of the TAD‐derived DA polymer. The self‐healing characteristics of this TAD‐derived DA conjugate are studied by monitoring the healing of a notched surface via AFM analysis. Interestingly, the TAD conjugated fluoropolymers are hydrophobic, as evidenced by the water contact angle analysis. Such TAD‐derived DA fluoropolymer conjugates with remarkable hydrophobic characteristics and excellent self‐healing features can pave a new direction in the potential materials for specialty paints, coatings, and adhesives. This article reports synthesizing a hydrophobic self‐healing fluoropolymer based on the rapid anthracene‐1,2,4‐triazoline‐3,5‐dione (TAD) Diels–Alder (DA) reaction. Herein, the BCPs of 2,2,2‐trifluoroethylmethacrylate and 2‐hydroxyethyl methacrylate are prepared via RAFT polymerization. The hydroxyl group‐containing BCP is modified with anthracenyl functionality and subsequently crosslinked using a bifunctional TAD derivative. The dynamic DA linkages endow facile healing characteristics on the TAD‐derived polymers.