Physical characterization of poly(glycerol sebacate)/Bioglass® composites

Differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA) and X-ray diffraction have been used to characterize the structure of a crosslinked polyester (poly(glycerol sebacate), PGS), prepared from a molar ratio of a diacid (sebacic acid) and a triol (glycerol), and their composites formed with an alkaline reactive filler, Bioglass (R). The Bioglass reacts with the sebacic acid carboxylate groups during the composite synthesis, resulting in elastomers that are linked by ionic and covalent crosslinks. Due to its relatively low crosslink density, the unfilled PGS polymer can crystallize below room temperature but is an amorphous elastomer at room temperature. The DSC results show that the Bioglass composites are also semicrystalline below room temperature but the crystallinity is disrupted by the ionic linkages. DMTA of the dry PGS and PGS-Bioglass composites confirms the semicrystalline nature of the materials and comparison with specimens that had been saturated with water vapour shows that the ionic crosslinks are dissociated by hydration by water molecules. Copyright (C) 2011 Society of Chemical Industry