New biodegradable polymers from renewable sources: Polyester-carbonates based on 1,3-Propylene-co-1,4-cyclohexanedimethylene succinate

alpha,omega -Dihydroxy-terminated copolymeric oligomers of a 1,3-propylene/ 1,4-cyclohexanedimethylene succinate structure were obtained by the thermal polycondensation of 1,3-propanediol/1,4-cyclohexanedimethanol/s acid mixtu res. They were subsequently chain-extended via phosgene synthesis to high m olecular weight aliphatic/alicyclic copolyester-carbonates. These new polym ers, besides having a biodegradable backbone, originate from two monomers, namely, 1,3-propanediol and succinic acid, which can be obtained by renewab le sources. Therefore, they have a potential as environmentally friendly ma terials. All synthesized materials were characterized in reference to their molecular structure by H-1 NMR and C-13 NMR. Their molecular weights and m olecular weight distributions were determined by size exclusion chromatogra phy, and their main thermal properties were measured by DSC. Spectroscopic characterizations were in full agreement with the proposed structures. 1,4- Cyclohexanedimethanol was used as a diol comonomer to improve the overall t hermal properties of poly(1,3-propylene succinate). The results of the char acterization performed show that the initial expectations were only partial ly satisfied. (C) 2001 John Wiley & Sons, Inc.