Sinomer® 4-META is a unique bifunctional monomer that serves as a powerful adhesion promoter. Its structure combines a polymerizable methacrylate group with a reactive anhydride group, enabling strong chemical bonding to substrates like metals and tooth structure while copolymerizing with resin systems. This amphiphilic nature promotes resin infiltration, making it essential for enhancing bond strength in dental adhesives, cements, and industrial applications such as photosensitive polyimides (PSPI) and specialty coatings.