Solution-Melt Polymerization Technique

Different approaches have been used to optimize the dispersion of CNTs in the polymeric medium. Composites can be prepared by different techniques including in-situ polymerization, solution mixing, surfactant-assisted processing and melt compounding. 

The two principal methods used for the synthesis of aromatic polyamides are interfacial polymerization and solution polymerization. Vapor-phase polymerization and plasticized melt techniques have also been demonstrated but have not been adopted for practical use. 

Polycondensation can be carried out by various polymerization techniques including melt polymerization, solution polymerization, interfacial polymerization, emulsion polymerization and solid-state polymerization. These polymerization processes will be summarized briefly in the following paragraphs. 

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. 

When obtaining PLA/clay nanocomposites, three main techniques are frequently used to produce nanocomposites of this material, namely in situ intercalative polymerization, solution-casting and melt mixing. Of the three, the in situ intercalative polymerization method exhibits the highest performance, since it is the one that results in a higher degree of interaction... 

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 1975, Kellyprepared and characterized a number of polyesters based on 2,5-disubstituted furans in various states of reduction. In this study, 2,5-disubstituted-furan, -dihydrofuran, and -tetrahydrofuran monomers were polymerized using solution, melt-transesterification, ring-opening, and interfacial techniques. These monomers included diacids, diols, diacid chlorides, diesters, dicarboxylic acid anhydrides, as well as monomers based on 5-hydroxymethyl-2-furoic and tetrahydrofuroic acids and esters, and bycyclic lactones containing the tetrahydrofuran ring. A thorough review of previous work done in the area of poljnner synthesis, based on 2,5-disubstituted furan derivatives is reported. It is reported that when... 

As discussed earlier, the predominant polymerization technique for PA 6.6 formation is the solution-melt process. However, despite the commercial importance of the latter process, few efforts have been reported to expand it on nanocomposites formation by in-situ polymerizing the monomers in the presence of the nanofiller. Notably, although the in-situ intercalation process has been extensively, successfully, and commercially applied for the preparation of lactam/amino acid-based nanocomposites, for example, PA 6, a different picture is presented in diamine-and diacid-based nanocomposites, for example, PA 6.6, mainly characterized by the poor pertinent literature and lack of commercial application. 

One of major changes for high performance polymer nanocomposites is to optimize the processing of CNT-reinforced polymer nanocomposites with low costs. Four processing techniques are in common use to fabricate the CNT/polymer nanocomposites direct mixing, solution method, in situ polymerization, and melt compounding [26-35]. Among these... 

PA 66 prepolymer is prepared through a solution-melt polymerization technique, starting from the aqueous PA 66... 

Solution blending, in situ polymerization, and melt blending are three processing techniques used for preparing polymer-layered silicate nanocomposites. In solution blending, a polymeric solution is prepared and layered silicates are swollen in a cosolvent (water, toluene, chloroform, etc.). By mixing the polymeric and silicate nanolayers solutions. 

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