Intercalation organoclays

Sepehr, M., Utracki, L. A., Zheng, X., and Wilkie, C. A., Polystyrenes with macro-intercalated organoclay Part II. Rheology and mechanical performance. Polymer, 46, 11569-11581... 

Zhou, Q., He, H., Frost, R. L., and Xi, Y. 2007. Adsorption of p-nitrophenol on mono-, bi-, and trialkyl surfactant-intercalated organoclays A comparative study. Journal of Physical Chemistry C 111 7487-7493. 

Fig. 5. Transmission electron microscopy of a melt-intercalated organoclay tactoid in a PP matrix. Courtesy of Dr M. Bacia, UST Lille.

M. Sepehr, L. A. Utracki, X. Zheng, and C. A. Wilkie, Polystyrenes with macro-intercalated organoclay. Part I. Compounding and characterization. Polymer, 46 (2005), 11557-68. 

In the case of rubber blend clay composites good state of exfoliation of the clay, sufficiendy strong filler-rubber interactions as well as the compatibility between different rubber phases are playing major role. The presence of intercalated organoclays restricts the mobility of the rubber chains due to their confinement between the layers. As the concentration of nano filler increases the loss modulus increased. This can be explained in terms of the friction between the filler particles and the rubber matrix when the filler particles are uniformly dispersed in the mbber matrix. The damping values are found to decrease with the amount of filler due to the restricted mobility of the polymer chains owing to the intercalation of polymer chains into the layers of silicates. 

FIGURE 7 The TEM bright field representative image of intercalated PLACNs. The dark entities are the cross section of intercalated organoclay layers, and the bright areas are the matrix. (Katiy ar et al., 2011) (Reprinted by the permission from authors). 

Unfortunately, however, the impact strength of die ternary nanocomposite is lower than that of the PBT/EVA-g-MAH blend. It should be noted, however, the uniform dispersion of the intercalated organoclay in the continuous PBT phase leads to higher tensile strength and modulus of the ternary nanocomposite compared to the PBT/EVA-g-MAH blend. It was also reported diat die thermal stability of the nanocomposite was improved in comparison to that of the PBT/ EVA-g-MAH blends, due to the clay layer structure. 

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