Preparation of polymer brush and patterned microstructures on gold

Polymethylmethacrylate brush on gold was prepared by surface initiated room temperature atomic transfer radical polymerization. The film thickness grew linearly with the polymerization duration. The reaction procedures were characterized by ATR-FTIR and XPS. XPS characterization verified the presence of initiation moiety at the end of polymer brush. Polymer brush could completely inhibit the redox reaction of K₃Fe(CN)₆ probe and so showed efficient electron blocking role. Photo-patterned PMMA brush was used as the template for generating polypyrrole (PPy) microstructures. After post UV treatment and wet chemical etching to remove the gap polymer brush and gold, freestanding PPy micro-arrays were obtained. The as-deposited PPy could prevent the underlying gold from dissolving in KI/I₂ etchant solution. Removal of PPy arrays by a molding/adhesion process left gold pattern on substrate.