Polycarbonates were synthesized by transesterification polymerization of isosorbide, bisphenol A, and diphenyl carbonate in the presence of n-BuSn(?O)OH as the catalyst. The polymers were prepared by varying the ratio of the two monomers. The polymers exhibited good thermal stability, rigidity, and strength. The storage moduli for the polymers were 2.6 to 3.2 GPa at 25 degrees C and increased with increasing isosorbide content. The dynamic mechanical analysis indicated that the storage moduli (E') of the polymers are constant to higher temperatures than that of bisphenol A polycarbonate. (C) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2012