Exfoliation behavior

Ratnayake, U. N. and Haworth, B. 2006. Polypropylene-clay nanocomposites Influence of low molecular weight polar additives on intercalation and exfoliation behavior. Polymer Engineering and Science 46 1009-1015. 

Lu JK, Ke YC, Qi ZN, Yi XS (2001) Studies of intercalation and exfoliation behavior of organoclays in epoxy resin. J Poym Sci Part B Polym Phys 39 115-120 Lotti C, Isaac CS, Branciforti MC, Alves RMV, Liberman S, Bretas RES (2008) Rheological, mechanical and transport properties of blown films of high density polyethylene nanocomposites. Eur Polym J 44 1346-1357... 

Figure 3.13 Evolution of the value of the absorbance of the peak located at 272 nm for an aqueous 0.1 wt% HiPCO CNT dispersion, containing 1 wt% of SDS. The SWCNTs for which the exfoliation behavior is monitored here come from a lower quality batch, and are exfoliated either before ( ) or after purification (O).

Xu, W.-B., Bao, S.-P., He, P.-S., 2002. Intercalation and exfoliation behavior of epoxy resin/ curing agent/montmorillonite nanocomposite. Journal of Applied Pol3Tner Science 84, 842-849. 

M., Leuteritz, A., Jehnichen, D Janke, A. et al. (2007) Exfoliation behavior of montmorillonite modified by poly (oxyalkylene)s in polypropylene and the properties of the resulting nanocomposites. Polymer Engineering and Science, 47,1262-1271. 

Nonequihbrium thermodynamic arguments by Rubi [6] and Onsager s reciprocity relationship could be applicable to the exfoliation behavior of Cloisite 15A as a function of processing conditions. The conditions that produced the exfoliated state for Cloisite 15A could represent a nonequilibrium thermodynamic state with the nonexfohated states representing conditions closer to equilibrium. The implications of nonequilibrium thermodynamics to exfoliation of montmorillonite in polymers will not be pursued because those arguments lie outside the scope of this chapter. 

Jiankun, L. et al. (2000) Study on intercalation and exfoliation behavior of organodays in epoxy resin. J. Polym. Sci. Part B Polym. Phys., 39, 115-120. 

This is a highly polar polymer and crystalline due to the presence of amide linkages. To achieve effective intercalation and exfoliation, the nanoclay has to be modified with some functional polar group. Most commonly, amino acid treatment is done for the nanoclays. Nanocomposites have been prepared using in situ polymerization [85] and melt-intercalation methods [113-117]. Crystallization behavior [118-122], mechanical [123,124], thermal, and barrier properties, and kinetic study [125,126] have been carried out. Nylon-based nanocomposites are now being produced commercially. 

It was shown that the clay dispersion was improved with increasing compatibilizing agent, but at the expense of the polymer processability into filaments. Nevertheless, there was no evidence of intercalation or exfoliation, irrespective of the nature of compatibilizer or clay modifier, nor strong improvements of LOI. Despite the absence of formation of true nanocomposites, filaments were sufficiently strong to be knitted into fabrics and presented slower burning behavior than the pure polymer. 

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