Preparation And Properties Of Polymer/Layered Double Hydroxides Composite Nano-Materials

Combination of polymer and inorganic is an essential part of nano-composites science and technology and also increasingly recognized as an important method of preparation of high-performance polymer materials. Polymer and inorganic, capable of combination at nano-and molecular level, and showing their respective strengths, have aroused great attention worldwide. Layered double hydroxides (LDHs) are a class of anionic layered functional materials in the field of catalysts, catalyst supports, stabilizers in polymer composites, drug delivery material, adsorbents for wastewater treatment, precursors for chemically tailored functional materials and matrix materials in hybrid composites.In the present study, we report on a facile protocol of preparing colloidal layered double hydroxide/polyvinyl alcohol (cLDH/PVA) electrospun nanofibrous mats via direct incorporation of low-content cLDH nanoplatelets with PVA without aid of any surfactant. The as-prepared cLDH/PVA nanofibrous mats exhibit a uniform, smooth surface, and enhanced temperatures of the onset decomposition and inflection compared to the electrospun mats of pristine PVA and solid powdery LDH/PVA (pLDH/PVA) with the same LDH content. Subsequent surface chemical modification enables the resulting cLDH/PVA fibrous mats to exhibit superhydrophobicity and adhesion to water droplets, which are distinctly different from the hydrophilicity of the unmodified cLDH/PVA fibrous mats. Our results involving the cLDH/PVA electrospun nanofibrous mats may allow designing a variety of electrospun composite nanofibers with homogenous morphology and multiple properties.On the other hand, SA/LDHs mesoporous composites were successfully fabricated by soft template method in the presence of biomolecule (sodium alginate, SA). The results indicate that SA may act as organic template to induce SA/LDHs mesoporous composites with very large specific surface area compare with pristine LDH. Moreover, due to the different concentration of SA in the preparation process, the as-prepared SA/LDHs mesoporous composites exhibited different morphologies, specific surface areas and location of the surface acid sites. When the concentration of SA reached to 1.5%, the SA/LDHs mesoporous composites exhibit the largest specific surface area and strongest surface acidity.