Solution-intercalation/mixing method

In the melt mixing method, nanoclays are incorporated into the polymer in the molten state. This technique has considerable advantages over either the in situ intercalative polymerization or polymer solution intercalation techniques. Firstly, this method is environmentally benign due to the absence of organic solvents. Secondly, melt processing is compatible with current industrial processes, such as extrusion and injection moulding. The melt intercalation method allows the use of biopolymers that were not suitable for in situ polymerization. This has been the most widely used method in the literature for obtaining PLA/clay nanocomposites. " ... 

This elaboration process is based on a solvent system in which the polymer is soluble and the nanoliller is sweUable. The polymer is first dissolved in an appropriate solvent. In parallel, the nanoliller is swollen and dispersed into the same solvent or another one to obtain a miscible solution. When the polymer and nanoliller solutions are mixed, the polymer chains intercalate and displace the solvent within the interlayer of the nanofiU. Upon solvent removal, the intercalated stmcture remains, resulting in a nanocomposite. In this method the nature of the solvents is critical in facilitating the insertion of polymer molecules between the nanoliller layers, polarity of medium being the determining factor for intercalation. Since some polysaccharides, such as cellulose or pectin, cannot be melt processed due to high thermal or thermomechaiucal degradation, the solvent process has been extensively used to produce polysaccharide/nanofiller hybrid materials. 

In the weak basic solution, Ni(OH)2 is preferentially formed in the interlayer space of blmessite rather than as free Ni(OH)2 from Ni containing solution. Hydrothermal intercalation method is favored the formation of a mixed layered Ni(OH)2-manganese oxide, in which the Ni(OH)2 insertion into the bimessites is topotactic reaction. 

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