In-Situ Intercalate

Keywords In-situ Intercalation Layered Double Hydroxide... 

Similarly to FeOCl, V205.nH20 is also capable of undergoing in situ intercalation/ polymerization. The intercalation of polyaniline, polypyrrole, and polythiophene into... 

VOPO4.2H2O is capable of undergoing in situ intercalation/polymerization with molecules such as aniline [50, 51], substituted anilines [52,53,54], and pyrroles [55]. Evidence of intercalation was obtained from powder X-ray diffraction. As an example, the powder pattern of poly(A-methylaniline) (PMA) intercalated into VOPO4 is illustrated in Figure 6.11. The identity of the intercalated polymer was confirmed by Fourier-transform infrared studies. 

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... 

Lactam/Amino Add-Based In-situ Intercalated PA Nanocomposites... 

PA 11-clay nanocomposites have also been reported through the in-situ intercalation method, by using 11-aminoundecanoic acid both as monomer and as clay organic modifier [63]. For less than 4wt% of clay loading, the nanofiller was uni-... 

Another nanofiller type that has been reported to form PAs nanocomposites by in-situ intercalation are CNTs. Gao et al. [64] prepared PA 6-single-wall carbon nanotubes (SWNTs) by in-situ polymerizing caprolactam in the presence of carboxylic acid-functionalized S WNTs (Figure 2.11). They reported an efficient dispersion of the nanofiller in the monomer and a subsequent grafting of the PA 6 chains to the CNTs, through a condensation reaction between the SWNTs carboxyl groups... 

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. 

The nanocomposites can also be formed using clay as reinforcing component. Some of the polymers having bend structure in the main chain have the advantage of lower transition temperature and mechanical properties. It will be ideal to make a clay nanocomposite to compensate for the loss. Among several methods for preparing polymer nanocomposites, in situ intercalation... 

Accordingly, a two-step method, named masterbatch process, has been approached for the preparation of PCL layered silicate nanocomposites by combining the in-situ intercalative polymerization and the melt blend intercalation process d. In such a process, a highly clay-filled (organo-modified) PCL is first prepared by in-situ intercalation pol)mierization of e-CL, followed by its addition as masterbatch, that is blended with the molten polyester matrix (commercial PCL CAPA 650). As it will be shown, this method permits to prepare PCL-based nanocomposites with a high degree of exfoliation, which cannot be achieved by directly mixing PCL and clay. 

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