2-Acrylamido-2-methyl-1-propanesulfonic acid (AMPS), and crotonic acid (CrA) copolymerized with different feed ratios using N,N-dimethylformamide as a solvent and benzoyl peroxide (Bz2O2) as an initiator at 70°C. Structure and composition of copolymers for a wide range of monomer feed were determined by elemental analysis (content of N for AMPS-units). Monomer reactivity ratios for AMPS (M1)-CrA (M2) pair were determined by the application of conventional linearization methods such as Fineman-Ross (F-R), Kelen-Tüdös (KT) and Extended Kelen- Tüdös (EKT) and a nonlinear error invariable model method using a computer program RREVM. The characterizations were done by Fourier transform infrared spectroscopy (FTIR), 1H-and 13C-NMR spectroscopy, differential scanning calorimetry (DSC) thermal gravimetry analysis (TGA), scanning electron microscopy (SEM), and X-ray diffraction. The antimicrobial effects of polymers were also tested on various bacteria, and yeast.