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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®. 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 © 2011 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this study, MgMn-layered double hydroxide (MgMnLDH) exhibited excellent remediation functionality for heavy metals-antibiotics combined pollution. On the one hand, Co 2+ and Cu 2+ was efficiently immobilized on MgMnLDH with maximum quantity of 4.30 and 10.65 mmol g -1 , respectively. A series of characterizations reflected the changes in structure and physicochemical properties of MgMnLDH after the immobilization. Density functional theory calculations (DFT) confirmed that the binding modes were lattice substitution for Co 2+ and surface precipitation for Cu 2+ . On the other hand, the immobilized heavy metals enhanced the heterogeneous degradation for sulfamethoxazole (SMX) by peroxymonosulfate (PMS) activation. Complete degradation was achieved within 10 min in MgMnLDH-Co-4/PMS system and 60 min in MgMnLDH-Cu/PMS system, while only 20% in MgMnLDH/PMS system. The pH adaptability, reusability, stability and activation mechanism of two systems were systematically compared. The superior degradation performance of MgMnLDH-Co-4 benefited from the intense Co/Mn synergism and abundant oxygen vacancies, which could accelerate electron transfer during PMS activation process. The applicability of two catalysis system was confirmed in purifying other antibiotics and actual wastewater. The results highlight the importance of structural control in heterogeneous catalysis and provide new idea for environmental remediation., (Copyright © 2020 Elsevier B.V. All rights reserved.)