The preparation of a series of copolymers of N-t-butylacrylamide (NTBAM) with acrylamide (AM) is reported. The insolubility of NTBAM in water led to tile testing of methanol, t-butanol, and mixtures of these solvents with water to obtain effective copolymerization. Several of these polymerizations produced nonhomogeneous product mixtures. Samples of the components were separated and characterized by photoacoustic Fourier transform infrared spectroscopy and C-13 NMR spectroscopy. Hydrodynamic volumes of the products were obtained from solution-viscosity measurements, gel permeation chromatography, and multi-angle laser light scattering methods. The NTBAM-co-AM copolymers had degrees of polymerization and molecular weights in the 4.1-5.9 x 10(4) monomer units and 3.25-4.5 x 10(6) g/mol range, respectively. They contained from 15 to 36 mol % NTBAM.