We report the synthesis and characterisation of a new family of high surface area and dispersible layered double hydroxides entitled Aqueous Miscible Organic Layered Double Hydroxide (AMO-LDH).

New nanocomposites have been prepared using unmodified polypropylene (PP) and a new type of highly dispersed [Zn2Al(OH6)][B4O5(OH)4]0.5 (Zn2Al-borate) and [Mg3Al(OH)8][B4O5(OH)4]0.5 (Mg3Al-borate) layered double hydroxides (LDHs). PP/LDHs nanocomposites with LDH loadings of 1, 3, 6, 9, 15, and 30 wt % have been prepared by a novel solvent mixing method. Scanning electron microscopy (SEM) analysis shows that the precipitated nanocomposites materials form spherical particles with an average size of ca. 10 μm and that the LDH nanoparticles were well dispersed within the PP matrix. XRD analysis of the nanocomposites indicates that the LDHs are completely exfoliated. The thermal stability and flame retardancy properties of these new materials have been evaluated as a function of the nature of LDH and the LDH loadings. Cone calorimetry analysis indicates that PP/Zn2Al-borate nanocomposites exhibited superior performance than the equivalent PP/Mg3Al-borate nanocomposites; a 15 wt % of the highly dispersed Zn2Al-borate LDH in PP was found to be the optimal loading. The 15% Zn2Al-borate LDH in pristine (unmodified) PP resulted in reduction of the PHRR (peak heat release rate) (Rdctn) by 63.7%. We also demonstrated that the solvent mixing is superior to a melt mixing method. With a 6 wt % LDH loading, the reduction in PHRR is 23.8% for the melt mixing sample, which is lower than that of solvent mixing sample (29.9%), this behaviour can be attributed to the severe aggregation and poor dispersion of LDH particles.

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One of the major challenges in the circular economy relating to food packaging is the elimination of metallised film which is currently the industry standard approach to achieve the necessary gas barrier performance. Here, we report the synthesis of high aspect ratio 2D non-toxic layered double hydroxide (LDH) nanosheet dispersions using a non-toxic exfoliation method in aqueous amino acid solution. High O 2 and water vapour barrier coating films can be prepared using food safe liquid dispersions through a bar coating process. The oxygen transmission rate (OTR) of 12 μm PET coated film can be reduced from 133.5 cc·m −2 ·day −1 to below the instrument detection limit (<0.005 cc·m −2 ·day −1 ). The water vapour transmission rate (WVTR) of the PET film can be reduced from 8.99 g·m −2 ·day −1 to 0.04 g·m −2 ·day −1 after coating. Most importantly, these coated films are also transparent and mechanically robust, making them suitable for flexible food packing while also offering new recycling opportunities.

Restoring order: YIII, EuIII, and ErIII tris(ligand) complexes of a new chiral alkoxide ligand, tBu2P(O)CH2CH(tBu)OH (HL), preferentially form as C3‐symmetric diastereomers. Thus racemic HL affords (RRR)‐ and (SSS)‐[LnL3] complexes, which are active catalysts for the stereoselective polymerization of rac‐lactide to afford highly isotactic polylactic acid.