Polymer–Layered Double Hydroxide Nanocomposites by Emulsion and Suspension Polymerization
LDHs, also known as anionic clays or hydrotalcite (HT)-like materials, are a family of materials consisting of positively charged brucite-like layers with intercalated anion and water molecules. The relatively weak interlayer bonding and excellent expanding properties of LDHs make them suitable for achieving well-dispersed nanocomposites through intercalation process like layered silicates. In the present chapter, we first give a brief review on the synthesis of LDHs, their organic modification, and the conventional strategies for preparing polymer/LDH nanocomposites. Then we summarize and discuss the up-to-date results obtained from the polymer/LDH nanocomposites prepared by emulsion and suspension polymerization in detail, including their synthesis, characterization, and potential applications.
Owing to their heterogeneous reaction systems, emulsion and suspension polymerization provide effective ways to achieve water-insoluble polymer /LDH nanocomposites in aqueous system. These strategies allow combining the nanocomposite synthesis procedure with the synthesis and modification procedure of LDHs in one system, which makes the production more efficient. Otherwise, the emulsion and suspension polymerization show many advantages, such as environment friendly, excellent heat control, low viscosity, and high molecular weight products obtained by fast polymerization rates. The nanocomposites obtained by emulsion and suspension polymerization exhibit enhanced thermal stability, improved flame retardancy, and good optical properties.