Preparation and characterization of novel naphthyl epoxy resin containing 4-fluorobenzoyl side chains for low-k dielectrics application

Abstract

A new type of epoxy monomer 1,5-bis(4-fluorobenzoyl)-2,6-diglycidyl ether naphthalene (DGENF) was obtained through a three-step procedure involving Friedel–Crafts acylation, demethylation, and followed by nucleophilic reaction. The chemical structures were confirmed by ¹HNMR, ¹⁹FNMR and FT-IR. After curing with methylhexahydrophthalic anhydride (MeHHPA), the properties of DGENF epoxy resin were measured and compared with three other kinds of commercial epoxy resins. As a result, DGENF exhibited excellent thermal stability, hydrophobic and dielectric properties. For example, DGENF had a higher glass transition temperature of 170 °C than the other three commercial epoxy resins. DGENF showed a higher contact angle of 116°, which could satisfy the standard of hydrophobic materials. In addition, DGENF showed significantly lower dielectric constant (2.97 at 1 MHz) and dielectric loss (0.0188 at 1 MHz) than those of the other commercial epoxy resins because of the introduction of fluorine on the side chains, which improved the electronegativity of the epoxy resin and reduced the polarizability of molecules efficiently. Herein, we believe the novel naphthyl epoxy resin (DGENF) has demonstrated potential application in electronic industries.