Piperazine-Containing Polymer Brush Layer as Supported Base Catalyst in a Glass Microreactor

The covalent attachment of piperazine onto the inner walls of a microreactor using glycidyl methacrylate polymer brushes has been demonstrated. The piperazine-containing polymer brushes were first grown on a flat silicon oxide surface and were characterized by contact angle, Fourier transform infrared (FT-IR), ellipsometry, and X-ray photoelectron spectroscopy (XPS). The applicability of the catalytic polymer brushes in a microreactor was demonstrated for the Knoevenagel and nitroaldol condensation reactions, and the synthesis of coumarin derivatives. The catalytic activity of the microreactor was still intact even after 2 months.