Polymer intercalated method

This is a highly polar polymer and crystalline due to the presence of amide linkages. To achieve effective intercalation and exfoliation, the nanoclay has to be modified with some functional polar group. Most commonly, amino acid treatment is done for the nanoclays. Nanocomposites have been prepared using in situ polymerization [85] and melt-intercalation methods [113-117]. Crystallization behavior [118-122], mechanical [123,124], thermal, and barrier properties, and kinetic study [125,126] have been carried out. Nylon-based nanocomposites are now being produced commercially. 

To overcome the problem of diffusion of cumbersome molecules (such as polymers) into the constrained interlamellar space of LDH, several methods have been employed, which are presented in Fig. 7. According to the general classification established by Schbllhorn et al. [35], there are three principal options to obtain a polymer intercalated inorganic host ... 

Recently, the authors of this chapter have prepared polymer/clay nanocomposites using a water-soluble hyperbranched aliphatic polyester (Bottom from Perstorp) [Decker et al., 2009]. The nanocomposites were prepared via a solution-intercalation method using deionized water as the solvent medium. The nanocomposite preparation recipe was similar to that used by Plummer et al. [2002]. There are several advantages of this system compared to many other polymer/clay nanocomposite systems. These include the fact that no surfactant is required, the polymer is amorphous, and a broad range of composites from 0 to 95 wt% can be easily prepared. This... 

As the typical layered compound, MnO provides the open structure for conjugated-polymer intercalation [55]. The typical preparation methods for organic-intercalated MnO is complicated because of the fussy steps [55-59] (i) The layered manganese oxide (or Birnessite-type manganese oxide) A MnO (where A is K, Na, etc.) is first prepared by a soft... 

Several techniques such as intercalation of polymer from solution, in-situ intercalative polymerization, melt intercalation, direct mixture of polymer and particulates, template synthesis, in-situ polymerization and solgel process, are being employed for the preparation of polmer-layered silicate nanocomposites. Among them the most common and important approaches are in-situ polymerization, solution-induced intercalation method, and melt processing method, which are briefly discussed below. 

Other methods to prepare nanocomposites include a solvent-assisted process, whereby a cosolvent is employed to help carry the monomer into the galleries and is subsequently removed from the polymer system, and direct polymer melt intercalation methods, which involve the direct addition of nanoclays to a polymer melt under shear conditions atelevated temperatures, allowing their direct exfoliationintothepolymer[5]. 

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. " ... 

In-situ intercalation method was reported by Toyota researchers for the synthesis of polyamide nanocomposites that led to the exponential growth in the nanocomposites research. For generation of polymer nanocomposites by this method, the layered silicate mineral is swollen in monomer. After swelling, the polymerization of the monomer is initiated. As monomer is present in and out of the filler interlayers, therefore, the generated stmcture is exfoUated or significantly intercalated. As the rate or mechanism of polymerization in and out of the filler interlayers... 

Various methods have been developed in order to prepare pol3uner-layered silicate nanocomposites. These include in situ polymerization, polymer intercalation in... 

A number of methods have frequently been employed in the production of nanocomposite materials. These include solution intercalation, melt intercalation, polymerization, sol-gel, deposition, magnetron sput-tering, laser, ultrasonication, supercritical fluid, etc. In PHA nanocomposite fabrication, solution intercalation and melt intercalation methods are the most widely explored procedures. However, use of in situ intercalative polymerization, supercritical fluids and electrospinning are shown to be promising and emerging techniques. The performance and quality of a nanocomposite depends on how well the nanofillers disperse or blend into the matrix. Therefore, these methods constitute different strategies to improve the composites thermo-mechanical and physico-chemical properties by enhancing efficient interactions between the nanofiller and the polymer matrices. 

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