Bio - based PBS copolyesters derived from a bicyclic D - glucitol

2,4:3,5-di-O-methylene-D-glucitol (Glux-diol) was used for the synthesis of poly(butylene 10 succinate) (PBS) copolyesters by melt polycondensation. Glux-diol possess a rigid bicyclic 11 asymmetric structure made of two fused 1,3-dioxane rings and two hydroxyl functions at the end 12 positions. Copolyesters were prepared over the whole range of compositions with molecular 13 weights varying from 26,000 to 46,000 g·mol and a random microstructure. The thermal 14 stability of PBS did not significantly alter with the presence of Glux units. The glass transition 15 temperatures (Tg) steadily increased from -28 to 80 oC along the whole copolyester series with 16 the insertion of Glux. On the contrary, melting temperature (Tm) and crystallinity decreased 17 because of lack of regularity of the polymer chain although copolyesters with contents of Glux 18 units up to 30 mole-% were semicrystalline. The stress-strain behavior changed according to 19 variations produced in thermal transitions. The replacement of 1,4-butanediol by Glux-diol 20 slightly increased both the hydrolytic degradability and the biodegradability of PBS. Compared 21 to other bicyclic sugar-based diols reported in the literature, Glux-diol appeared to be more 22 efficient in both increasing the Tg and enhancing the susceptibility to hydrolysis of PBS. 23 24