CHARACTERIZATION OF NEW COPOLYMERS MADE FROM METHACRYLATE AND METHACRYLAMIDE DERIVATIVES OF CHOLIC-ACID

New copolymers were prepared from methacrylate and methacrylamide deri vatives of cholic acid and methacrylic acid by free radical polymeriza tion in solution. The copolymers were characterized by solid-state C-1 3 NMR spectroscopy and differential scanning calorimetry. The copolyme rs all have a single glass transition temperature located between the glass transition temperatures of the two corresponding homopolymers. T he copolymers were found to be random, and the chemical composition in the final products was close to the original monomer composition in t he feed prior to polymerization. Water absorption measurements showed that the water absorption capacity of the copolymers increases from ab out 10% to about 35% with increasing molar ratio of methacrylic acid i n the copolymers.