A series of copolyanhydrides, consisting of 2,3,4,5-tetra-O-acetylgalactaric acid (AGA) and adipic acid
(AA) as monomer units, was polymerized. Synthesis of AGA monomer consisted of two steps. First,
O-acetylation of galactaric acid secondary hydroxyl groups was performed using acetic anhydride as a
reagent. Acetic anhydride was then further used as a reagent in the synthesis of diacetyl mixed anhydride
of AGA. Polymerizations were conducted as bulk condensation polymerization at 150 C. Thermal properties
of the copolymers varied depending on monomer composition. Increase in the AGA content had a
clear increasing effect on the Tg. A similar increasing effect was observed in Tm. The degree of crystallinity
decreased as AGA content increased. There was a slightly lowering tendency in the molecular weights of
the obtained polymers when the AGA content in the polymerization mixtures increased. The described
synthesis route shows that bio-based aldaric acid monomers are potential candidates for the adjustment
of thermal properties of polyanhydrides.