Malleable and self-healing rubbers covalently crosslinked by reversible boronic ester bonds

Abstract

Covalent cross-linking of rubbers is essential to obtain high elasticity, which plays a significant role in practical applications.

Tough and Self-Healing Waterborne Polyurethane Elastomers via Dynamic Hydrogen Bonds Design for Flexible Conductive Substrate Applications

“…10−13 In recent years, there has been extensive research and reporting on incorporating reversible bonds into polymer chains to confer repairability to materials. These include covalent reversible bonds, such as disulfide bonds, 14,15 T h i s c o n t e n t i s Diels−Alder (D−A) reactions, 16,17 boronic ester bonds, 18,19 acyl hydrazone bonds, 20 and diselenide bonds, 21 as well as noncovalent reversible bonds, such as hydrogen bonds, 22 coordination bonds, 23 π−π stacking, 24−26 ionic bonds, and others. 27 Among them, the hydrogen bond is a type of dipole− dipole interaction, and its strength depends on the nature of the donor and acceptor.…”

Recyclable, Self-Healing, and Highly Thermal Conductive Natural Rubber Nanocomposites Enabled by a Dynamic Covalent Network with Carboxylated Boron Nitride Nanosheets

“…7 Therefore, there is an urgent need to prepare NR composites with high thermal conductivity. Learning from nature, sacrificial dynamic interactions such as ionic bonds, 8 hydrogen bonding, 9 metal−ligand bonds, 10 Diels−Alder bonds, 11 boronic ester bonds, 12 imine bonds, 13 disulfide bonds, 14 etc., have attracted great interest in academia in recent years. The dynamic bonds can preferentially break and dissipate energy, which endows rubbers with enhanced mechanical performance and functional characteristics such as self-healing, sensing, and shape memory.…”

Solvent-Free Environmentally Friendly Method to Prepare Thermo-Reversible Fully Bio-Based Elastomers

“…Therefore, the search for a new cross-linking technology that allows rubber products to be recycled while having good performance is a new way to make the rubber industry sustainable. In the past few years, compared with traditional covalent bond polymer materials, polymer materials with self-healing and plasticity prepared by dynamic non-covalent bonds and covalent bonds have attracted more and more attention due to their adaptability and reversibility. ,, For example, self-healing and recyclable polymers can be constructed through non-covalent interactions (hydrogen bond interactions, , π–π interactions, ionic bonds, and coordination bonds) or reversible covalent dynamic bonds (transesterification, , imine bonds, disulfide metathesis reactions, , borate ester bonds, and acylhydrazone bonds).…”

“…In the past few years, compared with traditional covalent bond polymer materials, polymer materials with self-healing and plasticity prepared by dynamic non-covalent bonds and covalent bonds have attracted more and more attention due to their adaptability and reversibility. 13,18,19 For example, self-healing and recyclable polymers can be constructed through non-covalent interactions (hydrogen bond interactions, 20,21 π−π interactions, 22 ionic bonds, 23 and coordination bonds 24 ) or reversible covalent dynamic bonds (transesterification, 25,26 imine bonds, 27 disulfide metathesis reactions, 28,29 borate ester bonds, 30 and acylhydrazone bonds 31 ). Among these reversible covalent dynamic bonds, the Diels− Alder (DA) reaction occurs between electron-deficient dienes and electron-rich-conjugated dienes to produce a sixmembered cyclic olefin structure via a [4 + 2] cycloaddition reaction, which has long been known.…”