Transmission electron micrographs clays

Transmission electron micrographs show hectorite and nontronite as elongated, lath-shaped units, whereas the other smectite clays appear more nearly equidimensional. A broken surface of smectite clays typically shows a "com flakes" or "oak leaf surface texture (54). High temperature minerals formed upon heating smectites vary considerably with the compositions of the clays. Spinels commonly appear at 800—1000°C, and dissolve at higher temperatures. Quartz, especially cristobalite, appears and mullite forms if the content of aluminum is adequate (38). 

Figure 2. Transmission electron micrograph of a Co/Al chlorite phase, Al/Al+Si = 0.4. a) Air-dried sample, b) Calcined at 600 C, 3h,showing small particles of spinel phase decorating edges of hexagonal clay platelets.

Figure 12.14 Transmission electron micrographs (varying magnification as indicated by scale bars) of (a) TPO-0 (Owt% clay), (b) TPO-1 (0.6 wt% clay), (c) TPO-3 (2.3 wt% clay), and (d) TPO-6 (5.6 wt% clay). EPR-rich rubbery domains (elliptically shaped) surrounded by clay platelets (dark rodlike structures) are clearly seen. (From Reference 42 with permission from John Wiley Sons, Inc.)...

The clay platelets may not exfoHate fully in melt blending technique. Homogeneously exfoliated clay platelets can be obtained in in-situ polymerized polyamide nanocomposites [54]. These structrues can be observed only from transmission electron micrographs, since the XRD patterns may... 

Figure 2.7 Transmission electron micrographs of armored latexes, (a) Sealed clay on poly(butyl acrylate) template particles ...

The synthesis of a PS/Montmorillanite clay nanocomposite prepared by combining methods 2 and 6 described earlier was published (137) (Fig. 21). They utilized living free-radical polymerization (LFRP) of styrene to provide exfoliated platelets in a PS matrix. Transmission electron micrographs and x-ray diffraction patterns support the idea of preparing nanocomposites via polymerization initiation. 

Figure 20.15 Transmission electron micrographs for selected nanocomposites prepared from clay and PA6 using different extruders and screw configurations. Dennis et al. [273], Reproduced with permission of Elsevier.

Figure 13.7 Transmission electron micrograph of ultrathin section of iPP based nanocomposite with 5 wt% of exfoliated o-MMT (Cloisite 15A, Southern Clay Products Gonzales, TX, USA) compatibilized with 10 wt% of PP-g-MA.

Figure 1. Packets of layers of a weathered mica-vermiculite clay particle from a Nason soil (Virginia) as seen in a transmission electron micrograph of an ultramicrotome section (prepared by J. L. Brown, Georgia Institute of Technology, Atlanta, Georgia).

Figure 13.6 Transmission electron micrograph of vinyl ester/clay nanocomposite containing 0.5 wt% organically treated montmorillonite. The magnification is 100,000 x. (From Ref 37.)...

Fig. 3.13 Images of halloysite clay, (a) Transmission election micrograph of tubes dispersed in water and dried on a copper grid (b) Scanning electron micrograph of dry HNT powder (Wei et al. 2014) Reproduced with permission of The Royal Society of Chemistry ]...

The state of clay dispersion into the matrix material was characterized by transmission electron microscopy (TEM) achieved on ultra-thin sections of specimens machined from compression-molded plates. TEM micrographs (see Fig. 1) confirmed that the nanocomposites produced using Cloisite SOB (PAC nanocomposites) exhibit exfoliated structures while untreated clay (PANM nanocomposites) leads to intercalated structures. The better clay dispersion into the matrix material in the PAC nanocomposites is a consequence of stronger interactions between constituents due to the functionalization used for the organophilization. 

Figure 5.109. Transmission electron microscopy micrographs of cryomicrotomed sections of a nylon/clay nanocomposite produced by continuous chaotic blending forms layers of oriented platelets and matrix polymer. (From Zumbrunnen et al. [502, 503] used with permission of the Society of Plastics...

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