Orthogonal Agent Comprising a Nitrile <i>N</i>‐Oxide and a Phenylcarbamate for Facile Molecular Integration on Styrne‐Butadiene Resin

The covalent attachment of poly(ethylene glycol) (PEGylation) to materials minimizes non-specific fouling of the material surface with biocomponents. While the PEGylation reaction on polar surfaces is widely used and regarded as a common technique, the PEGylation on less polar polymers and elastomers is extremely difficult due to the absence of reactive points with PEG terminus. Herein, the design and synthesis of an orthogonal agent with a nitrile N-oxide and a phenyl carbamate that can mediate between an alkene and an amine are reported. The ligation capacity of the orthogonal agent is demonstrated through the model reaction to connect between 1-hexene and 4-methoxybenzylamine and the grafting reaction of PEG onto poly(styrene-co-butadiene) (SB) resin. The surface characteristics of PEGylated SB film are evaluated by X-ray photoelectron spectroscopy (XPS) and contact angle measurements. Because SB resin is frequently used as a 3D-printing polymer, the present study indicates that the orthogonal agent can be applicable to the surface modification of 3D-printed objects precisely manufactured by using a computer-aided design (CAD) file in the future.