Cloisites

Maiti and Bhowmick reported exciting results that a polar matrix like fluoroelastomer (Viton B-50) was able to exfoliate unmodified clay (Cloisite NA ) as well as the modified one (Cloisite 20A) [93]. They studied morphology, mechanical, dynamic mechanical and swelling properties of fluoroelastomer nanocomposites. The unmodified-clay-filled systems showed better properties than the modified ones (Table 2.3). 

FIGURE 2.14 Tapping mode phase morphology of the nanocomposites (a) poly[styrene-(ethylene-co-butylene)-styrene] (SFBS)-Cloisite 20A and (b) its 3D image. (From Ganguly, A., Sarkar, M.D., and Bhowmick, A.K., J. Polym. ScL, Part B Polym. Phys., 45, 52, 2006. Courtesy of Wiley InterScience.)... 

Figure 15.2 (A) XRD patterns of Cloisite Na (a). Thermoplastic starch TPS (b), and the TPS/Cloisite Na" hybrid (c). (Source Park et al., 2002). (B) TEM images of TPS/clay hybrids of different kinds of clay, (a) TPS95/Cloisite Na, (b) TPS95/Cloisite 6A, (c) TPS95/Cloisite 10A, (d) TPS95/Cloisite SOB. (Reproduced with kind permission from Park et al., 2002, Wiley-VCH Verlag GmbH Co. KGaA).

Another example of enhanced flammability properties was obtained by adding POSS to the coating of textile fabrics.40 In this study, POSS was used as an additive for the PU resin and the product was applied as a coating to the polyester fabrics. For comparison purposes, another kind of additive (Cloisite 30B) has been used. The structure of POSS materials employed in this investigation... 

FIGURE 11.11 (See color insert following page 530.) Thermal stability of Cloisite 30B seen in XRD patterns before and after heating at 190°C under air for 15 and 30min (inset) TGA result under N2 at 20°C/min. 

FIGURE 11.17 XRD patterns of two organoclays (Cloisite 10A, from Southern Clay Products, and VB166a) and two PSCNs with intercalated (PS/10A) or exfoliated (PS/VB16) morphology. 

Incorporation of modified clays into thermosetting resins, and particularly in epoxy35 or unsaturated polyester resins, in order to improve thermal stability or flame retardancy, has been reported.36 A thermogravimetric study of polyester-clay nanocomposites has shown that addition of nanoclays lowers the decomposition temperature and thermal stability of a standard resin up to 600°C. But, above this temperature, the trend is reversed in a region where a charring residue is formed. Char formation seems not as important as compared with other polymer-clay nanocomposite structures. Nazare et al.37 have studied the combination of APP and ammonium-modified MMT (Cloisite 10A, 15A, 25A, and 30B). The diluent used for polyester resin was methyl methacrylate (MMA). The... 

Member Compositional Matrix of Polystyrene (PS) Containing Various Levels of a 3 1 Mass Ratio of Ammonium Polyphosphate (APP/PER (3 1)) or a Cloisite 15A Organoclay... 

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