In this work, the synthesis of PNIPAM, PMAA, and PNIPAM-PMAA copolymer brushes was carried out using surface-initiated atom transfer radical polymerization (ATRP). To facilitate polymerization from gold substrates, a thiol self-assembled monolayer was first deposited and then a bromine-based initiator was attached. The grafted polymer brushes were characterized using contact angle measurements, ellipsometry, and external reflectance Fourier transform infrared spectroscopy (ER-FTIR). Additionally, we investigated the pH and temperature responses of PNIPAM, PMAA, and the PNIPAM-PMAA copolymer using in situ, real-time ellipsometry measurements.