Chemical welding of polymer networks

Chemical welding as an attractive joining technique refers to the process that occurs through the formation of new chemical bonds between neighboring molecules at the contacting surfaces. To avoid ambiguity, various welding techniques applied for joining polymer materials were first outlined. The issues and challenges related to the chemical welding technique, basic ideas, and requirements for the chemical structure of polymer networks have been critically evaluated. The review summarizes the current state of chemical welding of vitrimer epoxies (VEs) designed to achieve welding behavior. The chemical welding of VEs occurs through bond-exchange reactions, which leads to the formation of reversible associations (bridges) in the welding zone. Furthermore, recent progress in the chemical welding of VE-based composites and blends is discussed. The most common techniques (solvent-assisted, thermal- and light-induced) and processing parameters are briefly described. Future research opportunities based on the gap in the field of chemical welding of VEs are also deliberated.