Design and fabrication of mechanically strong and self-healing rubbers via metal-ligand coordination bonds as dynamic crosslinks. (3rd May 2021)

• Record Type: Journal Article
• Authors: Cao, Liming; Gong, Zhou; Liu, Cong; Fan, Jianfeng; Chen, Yukun
• Is Part Of: Composites science and technology. Volume 207(2021)
• Publication Date: 2021-05-03
• Subjects: Epoxidized natural rubber -- Self-healing behavior -- Coordination bonds -- Strain sensing behavior; Composite materials -- Periodicals; Composite materials; Fibrous composites; Periodicals; 620.118
• DOI: 10.1016/j.compscitech.2021.108750
• Languages: English
• ISSNs: 0266-3538

Abstract

Abstract: Developing mechanically strong and efficient self-healing rubbers is booming and shows great potential in a wide range of applications. Herein, by introducing pyridine ligands onto rubber chains via ring-opening reaction between epoxy groups and aminopyridine, we constructed dynamic Fe 3+ -pyridine coordination bonds in commercially available epoxidized natural rubber (ENR). The reversible nature of the coordination bonds endows the rubbers with efficient self-healing behavior under moderate conditions. Meanwhile, the coordination bonds can also serve as crosslinking points, which enhanced mechanical properties of the fabricated rubbers. When the molar ratio of Fe 3+ to pyridine was 1 : 4, the tensile strength and 100% modulus reached 2.23 and 0.78 MPa, which are 18-times and 8-times that of the neat sample. Noteworthy, the sample also shows excellent self-healing capability with healing efficiency of 87% (tensile strength). Furthermore, by embedding conductive materials, we designed a conductive rubber with sandwich structure, which exhibits sensitive strain sensing behavior in detecting small strains. Graphical abstract: Image 1