Copolyesters from 1,4-butanediol, dimethyl terephthalate and either 2,3:4,5-di-O-methylene-galactitol or dimethyl 2,3:45-di-O-methylene-galactarate with compositions of 10, 20, 30, 40 and 50% of either galactitol or galactarate units were prepared by melt-polycondensation. The copolyesters had M-w in the 32,000-41,000 g mol(-1) range and had a random microstructure. They displayed T-g from 20 to 70 degrees C with values steadily decreasing with the content in galactarate units but increasing with the content in galactitol units. All the copolyesters were semicrystalline with T-m between 115 and 210 degrees C and they adopted the crystal structure of PBT. Copolyesters containing up to 20% of galactitol units as well as all galactarate copolyesters were able to crystallize from the melt, at a crystallization rate that decreased with the content in carbohydrate-based units. Stress-strain essays revealed an increment in the tensile strength and elastic modulus with increasing contents in galactitol units whereas these parameters decreased when galactarate units were the replacing ones. (C) 2012 Elsevier Ltd. All rights reserved.