A green functional nanohybrid: preparation, characterization and properties of a β-cyclodextrin based functional layered double hydroxide

Aiming to develop a multifunctional layered double hydroxide (LDH), a novel bio-based multifunctional anionic modifier, a beta-cyclodextrin (beta-CD) derivative functionalized with a controllable carbon-carbon double bond (C=C) (DB-CD-BS), has been designed, synthesized and used for the in situ synthesis of the functional LDH. The structure of the anionic beta-CD-based modifier was characterized by Fourier transform infrared spectroscopy (FTIR) and H-1 nuclear magnetic resonance (H-1 NMR). The H-1 NMR results showed the amount of C=C in the beta-CD-based modifier structure (DB-CD-BS) was controlled by the stoichiometric offset of the reagents. The DB-CD-BS intercalated MgAl-LDHs were prepared via a one step method and characterized by FTIR, Raman, X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), elemental analysis (EA), and microscale combustion calorimetry (MCC), respectively. The investigated results illuminated that the DB-CD-BS intercalated LDH showed an increase of the interlayer distance, plate-like morphology with rough edges and good thermal stability. In comparison with the conventional organic modified LDH (DBS-LDH), the MCC results showed DB-CD-BS intercalated LDH (DB-CD-BS-LDH) showed a significant decrease in heat release rate (HRR) and the total heat release (THR) as compared to the corresponding results from DBS-LDH, indicating the DB-CD-BS has low flammability.