Preparation Of Polythene/Layered Double Hydrotalcide Nanocomposites

Polymer/inorganic layered nanocomposites have attracted much attention and became one of the most promising fields of material science because of their excellent properties. Layered double hydrotalcides (LDHs) thanks to their unique layered structure and anion exchangeability, can be used as the inorganic host to prepare polymer/inorganic layered nanocomposites. Polymer/LDH nanocomposites have attracted much attention because of their prospective applications in absorption, ion exchange, catalyzing, light, electricity and magnetic fields.In this paper, LDH was modified with sodium dodecyl sulfate (SDS) by coprecipitation method and regeneration method. Much attention was paid to sintering temperature and regeneration time to find optimal synthesis conditions. The structure and properties of modified LDH were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TG). Composites were prepared with addition of LDH or modified LDH in polyethylene (PE) by melt blending. The investigations were made on the structure of composites and their thermal stabilities and mechanical properties. The following conclusions were collected. (1) Modified LDH could be successfully obtained both by coprecipitation method and regeneration method.The later was found to be in favor of forming crystalline modified LDH with more regular layered structure. (2) The interlayer space of modified LDH increased to 2.7 nm from 0.7 nm of the prestine LDH. The paticle size seemed to increase to some extent after interlay modification. In comparison with LDH, the modified one presented more weight loss in TG analysis. (3) Nanocomposites with exfoliated structure were prepared with modified LDH, while ordinary composites were obtained with addition of LDH of unchanged layer structure. (4) Nanocomposites of PE and modified LDH showed better thermal stability and mechanical properties than composites of PE and LDH.