Progress in preparation of high‐performance and multi‐functional polymer foams

Abstract Polymer foams are widely used owing to their distinctive cell structure and properties. However, polymer foams prepared by traditional foaming technologies are mainly from commodity polymers due to the difficulties of foaming at high temperature and have the problems such as poor mechanical properties and heat resistance, limited composition and functions, susceptibility to combustion, and challenges in achieving flame retardancy. This article presented a comprehensive review of our research on polymer foams that exhibit high performances and multiple functions. The study encompassed advanced foaming equipment, high‐temperature foaming of supercritical carbon dioxide, foaming of polymer‐based micro/nano‐functional composites, microwave selective sintering and foaming, as well as the development of novel polymer foams derived from engineering plastics and special engineering plastics, water‐soluble poly(vinyl alcohol), and multi‐functional polymer composites, which could not be prepared by the traditional foaming technologies. These advancements broaden the potential application fields of polymer foams.