Research Progress on the Synthesis of Hydroxyethyl Methacrylate <italic>via</italic> Ring-Opening Reaction Method

As the demand for high-performance polymeric materials and medical functional materials continues to grow, increasing attention has been devoted to reactive acrylate monomers bearing dual functional groups. Hydroxyethyl methacrylate (HEMA), which contains a polymerizable vinyl group and a reactive hydroxyl group, exhibits excellent biocompatibility and polymerization performance, making it widely applicable in dental materials, contact lenses, coatings, and adhesives. In recent years, several synthetic routes for HEMA have been developed, including direct esterification, transesterification, the chlorohydrin process, and epoxide ring-opening reactions. Among these methods, the epoxide ring-opening route has emerged as the predominant industrial process owing to its high atom economy and stable product quality. This article reviews the principal HEMA synthesis pathways, with particular emphasis on recent advances in catalytic systems and purification technologies associated with the epoxide ring-opening method, and discusses the key technical challenges and future development trends in this field.