Preparation and properties of diolefin rubber based on dynamically reversible bonding crosslinking

Abstract Endowing polymers with self‐healing properties holds great promise for extending the life of materials and reducing environmental pressure. However, it is still a challenge to have both mechanically enhanced and self‐healing properties. Dynamic reversible bonds can be broken and regenerated in response to external stimuli, thereby repairing localized cracks in the rubber matrix during use. Click reaction is an efficient and facile way to prepare self‐healing rubbers with dynamic reversible bonds. Herein, we have obtained a self‐healing styrene–butadiene rubber (SBR) (SLA) by introducing dynamic disulfide and hydrogen bonds in an “imitative” click reaction via using SBR as a model compound and lipoic acid (LA) as the cross‐linking agent. The mechanical properties and self‐healing capacity of SLA can be altered by adjusting the LA content. Furthermore, SLA‐Zn was further prepared by introducing Zn 2+ to form metal‐oxygen coordination bonds with carboxyl groups. The effect of Zn 2+ on the mechanical and self‐healing properties has been systematically investigated. Compared with SLA, SLA‐Zn has better mechanical properties and self‐repairing ability, with a tensile strength up to 3.85 MPa and a repair efficiency of about 76%. This facile preparation method paves the way for the development of low‐cost self‐healing diolefin rubbers.