Hydrophilic-hydrophobic biodegradable polymers: release characteristics of hydrogen-bonded, ring-containing polymer matrices

Synthesis and Characterization of Saturated and Unsaturated Poly(Alkylene Tartrate)s and Further Cross-Linking

Saturated and unsaturated polyesters based on l-tartaric acid were prepared and characterized. Two kinds of low molecular weight polyesters were synthesized by the reaction of l-tartaric acid and 1-12 dodecandiol and 1-8 octanediol. Three different kinds of low molecular weight unsaturated polyesters were synthesized by the reaction of l-tartaric acid, 1-12 dodecandiol, and maleic anhydride. The saturated and unsaturated polymers were characterized by means of proton nuclear magnetic resonance (H NMR), infrared analysis (IR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). These functionalized polymers were thermally cross-linked in the presence of a radical initiator and with 2-hydroxyethyl methacrylate (HEMA) and/or polyethylene glycol ethyl ether methacrylate) (PEGEEM) to prepare cross-linked polymers for biomedical applications. The films were characterized by means of DSC, TGA, and FTIR. The glass transition temperatures (Tg) of the polymers increase with increasing alkene group length and for the presence of the double bonds. The transition temperatures of the cross-linked films range from about -50°C, for the films contraining PEGEEM, to about 90°C, for the film containing HEMA.