A self-healing polydimethylsiloxane elastomer with high strength and high modulus

High-strength self-healing polydimethylsiloxane (PDMS) elastomers play an important role in harsh environments. How to increase the strength of self-healing PDMS is a major challenge for the development of self-healing polymers. The acylsemicarbazide (ASC) moieties that provide dynamic reversibility and multiple hydrogen bonds can impart excellent mechanical properties to the polymer matrix in a dynamic state, but the large polarity difference between the ASC group and the PDMS affects the aggregation structure of the material, thereby affecting the performance of the material. How to introduce ASC groups with different polarity into PDMS remains largely unexplored. Here, we propose a synthetic strategy to successfully prepare a transparent, self-healing PDMS elastomer with a record tensile strength (17.2 MPa), an ultra-high elastic modulus (20.1 MPa) and a good self-healing efficiency of 80%. This high-strength, high-modulus PDMS not only allows it to be used in more demanding environments, but also can serve as reversible adhesives for bonding transparent sheets due to its unique transparency. [Display omitted] •We introduce ASC groups with different polarity into PDMS.•The dynamic PDMS elastomer we prepared has a record tensile strength (17.2 MPa).•We found reprocessing will result in more rigid mechanical properties of the PDMS.