Mussel-inspired, self-healing polymer blends. (3rd June 2020)

• Record Type: Journal Article
• Authors: Song, Shengju; Yang, Haoyu; Cui, Yijie; Tang, Yifeng; Chen, Yanzheng; Yang, Biao; Yuan, Jikang; Huang, Jijun
• Is Part Of: Polymer. Volume 198(2020)
• Publication Date: 2020-06-03
• Subjects: Mussel adhesive proteins -- Dopamine methacrylamide -- Self-healing -- Polymer blends -- Catechols; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; 547.7
• DOI: 10.1016/j.polymer.2020.122528
• Languages: English
• ISSNs: 0032-3861

Abstract

Abstract: Reversible dynamic covalent and noncovalent interactions are widely used to generate intrinsically self-healing polymers. However, nearly all approaches require sophisticated design and multi-stepped, tedious synthesis limited to weak hydrogels and rubbers, and pre-assume that high-modulus materials are more difficult to heal than low-modulus ones. Inspired by mussel foot proteins with the special amino acid unit of 3, 4-dihydroxy-l -phenylalanine, we develop a paradigm for achieving self-mendable polymer blends, composed of polyurethane (PU) as the matrix and poly(dopamine methacrylamide) (PDMA) as the dispersed phase. Healing efficiency increases from 24 to 32% for neat PU to 80–90% for the blends with increased moduli. This paradigm provides new insights into the role of mechanical properties in determining self-healing: high mechanical properties do not necessarily weaken self-repairability. The proof-of-concept enables easy modification of soft materials by solution mixing them with a polymer containing catechol groups, and thus opens up new applications in coatings, adhesives, antifouling, and biological engineering. Graphical abstract: Multiple adhesive proteins of mussels inspire to form polymer blends via solution polymerization. These blends are self-healable though the matrix of polyurethane contains no catechols, implying the essential roles of catechols in the dispersed phase (i.e., polydopamine methacrylamide) in rendering mendability. Image 1 Highlights: Poly(dopamine methacrylamide)/polyurethane blends were formed via solution polymerization. These PDMA/PU blends achieve superior self-healability even though the matrix contains no catechol groups. Self-healing is dominantly determined by the availability of PDMA rather than by mechanical properties.