# Pnictogen-bonding-crosslinked polymer networks: constructing self-healing materials

## TL;DR

This paper introduces a new type of self-healing polymer material using pnictogen bonding, which offers better stability and healing properties compared to traditional hydrogen-bonded materials.

## Contribution

The first use of pnictogen bonding as a crosslinking motif in polymer networks to achieve tunable self-healing and enhanced stability.

## Key findings

- Pnictogen-bonded networks show greater topological stability than hydrogen-bonded networks.
- Materials with pnictogen bonding exhibit tunable self-healing in various environments.
- NMR and cocrystal studies reveal the mechanistic role of pnictogen bonding in polymer networks.

## Abstract

Herein, we introduce pnictogen bonding interaction into polymer networks for the design and modulation of dynamic macromolecular materials. Several types of polymeric pnictogen-bonding networks with graded interaction strengths were constructed to explore the structure–property relationship. Comprehensive investigations revealed that strengthening the pnictogen bonding significantly enhances the topological stability of the resulting materials. In contrast, analogous hydrogen-bonded networks did not exhibit comparable mechanical reinforcement. Moreover, the pnictogen-bonding networks endow the materials with tunable self-healing capability, allowing not only spontaneous healing at room temperature and thermally triggered healing on demand, but also effective healing in aqueous environments. This represents the first exploration of self-healing behavior driven by pnictogen bonding in polymeric materials. Mechanistic insights into the role of pnictogen bonding in polymer networks were elucidated through NMR titration of donor–acceptor polymer pairs, comparative self-assembly behavior, and cocrystal structures of small-molecule analogues. The incorporation of pnictogen bonding interaction into polymer networks provides a robust and versatile platform for engineering high-performance dynamic polymeric materials.

The pnictogen-bonding interaction is presented for the first time as a novel crosslinking motif for constructing dynamic polymer networks with enhanced topological stability and tunable self-healing performance.