Room-Temperature Self-Healable Blends of Waterborne Polyurethanes with 2-Hydroxyethyl Methacrylate-Based Polymers

• Published in: International journal of molecular sciences 2023-01, Vol.24 (3), p.2575
• Main Authors: Tzoumani, Ioanna, Iatridi, Zacharoula, Fidelli, Athena M, Krassa, Poppy, Kallitsis, Joannis K, Bokias, Georgios
• Format: Article
• Language: English
• Subjects: 2-hydroxyethyl methacrylate; Biosensors; Chemical bonds; Contact angle; Copolymers; glycidyl methacrylate; Hydrogen; Hydrophilicity; Hydrophobicity; N,N-dimethylacrylamide; NMR; Nuclear magnetic resonance; Polyhydroxyethyl methacrylate; Polymer blends; Polymer matrix composites; Polymers; Polymers - chemistry; Polyurethane; Polyurethanes; Room temperature; Self healing materials; Smart materials; Spectrum analysis; Temperature; Vibration; Water - chemistry; Water damage; Water drops; Water uptake; waterborne polyurethane
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms24032575

The design of self-healing agents is a topic of important scientific interest for the development of high-performance materials for coating applications. Herein, two series of copolymers of 2-hydroxyethyl methacrylate (HEMA) with either the hydrophilic , -dimethylacrylamide (DMAM) or the epoxy group-bearing hydrophobic glycidyl methacrylate were synthesized and studied as potential self-healing agents of waterborne polyurethanes (WPU). The molar percentage of DMAM or GMA units in the P(HEMA-co-DMAMy) and P(HEMA-co-GMAy) copolymers varies from 0% up to 80%. WPU/polymer composites with a 10% / or 20% / copolymer content were prepared with the facile method of solution mixing. Thanks to the presence of P(HEMA-co-DMAMy) copolymers, WPU/P(HEMA-co-DMAMy) composite films exhibited surface hydrophilicity (water contact angle studies), and tendency for water uptake (water sorption kinetics studies). In contrast, the surfaces of the WPU/P(HEMA-co-GMAy) composites were less hydrophilic compared with the WPU/P(HEMA-co-DMAMy) ones. The room-temperature, water-mediated self-healing ability of these composites was investigated through addition of water drops on the damaged area. Both copolymer series exhibited healing abilities, with the hydrophilic P(HEMA-co-DMAMy) copolymers being more promising. This green healing procedure, in combination with the simple film fabrication process and simple healing triggering, makes these materials attractive for practical applications.