Coating metal foil with N-heterocyclic carbene compounds containing organic functionalities for improving metal-to-resin adhesion

摘要

A carbene-coated metal foil is produced by applying an N-heterocyclic carbene (NHC) compound to one or more surfaces of a metal foil (e.g., an electrodeposited copper foil having a surface that is smooth and non-oxidized). The NHC compound contains a matrix-reactive pendant group that includes at least one of a vinyl-, allyl-, acrylic-, methacrylic-, styrenic-, amine-, amide- and epoxy-containing moiety capable of reacting with a base polymer (e.g., a vinyl-containing resin such as a polyphenylene oxide/triallyl-isocyanurate (PPO/TAIC) composition). The NHC compound may be synthesized by, for example, reacting a halogenated imidazolium salt (e.g., 1,3-bis(4-bromo-2,6-dimethylphenyl)-4,5-dihydro-1H-imidazol-3-ium chloride) and an organostannane having a vinyl-containing moiety (e.g., tributyl(vinyl)stannane) in the presence of a palladium catalyst. In some embodiments, an enhanced substrate for a printed circuit board (PCB) is produced by laminating the carbene-coated metal foil to a substrate that includes glass fiber impregnated with the base polymer.