The rise of phosphate ester exchange in developing dynamic covalent networks: Advances and challenges

Traditional thermosetting plastics are composed of permanent covalent crosslinked networks, which contribute to plastic waste issues that contradict the principles of sustainable economic development. In response to this dilemma, dynamic covalent networks (DCNs) have emerged as a potential solution by incorporating dynamic covalent bonds into polymer networks. Numerous researchers have dedicated their efforts to developing DCNs through various chemistry mechanisms. This review paper delves into the latest research on DCNs development based on phosphate ester exchange, with particular attention given to the dynamic properties of materials, such as malleability and recyclability, as well as mechanical and flame-retardant properties. Of particular interest is the DCNs design that employs β-hydroxy phosphate ester transesterification, as the β-hydroxyl group exhibits a molecular-level neighboring effect, eliminating the need for additional catalysts within the system. In conclusion, this review aims to identify current challenges within the field and offer a foundational understanding of the existing research on DCNs development and applications.