Effect of electric field on polymer/clay nanocomposites depending on the affinities between the polymer and clay

Abstract

Applying an electric field is an efficient way to fabricate polymer/clay nanocomposites. It helps to achieve a good dispersion of nanoclays which improves the performance of the polymeric system. In this study, the effect of an alternating current (A.C.) electric field was investigated on clay exfoliation with various combinations of polymer/clay nanocomposites. Three different types of organoclays (Cloisite 10A, 20A, 30B) were introduced in polypropylene (PP) and poly(lactic acid) (PLA) matrices. Their rheological properties showed that the A.C. electric field was effective in enhancing the dispersion of organoclays in both the PP/clay and PLA/clay composites. The efficiency of the A.C. field varied depending on the combination of polymer and clay nanoparticles. In the case of PP, the best combination was PP/C20A followed by PP/C10A and PP/C30B. In contrast, PLA/clay showed an opposite trend. This difference arises from the different affinities between the polymers and the functional groups of the clays. The Hansen solubility parameter was introduced to quantify the affinities between the polymer and clay. The electric field was more effective for polymer/clay combinations that had less difference in the Hansen solubility parameter. V C 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43582.

Evaluation of the Degree of Dispersion of Polymer Nanocomposites (PNCs) Using Nonlinear Rheological Properties by FT-Rheology

“…Diverse efforts have been made to improve filler dispersions in PNCs, which are usually synthesized by intercalation of polymer or prepolymers from solution, in situ intercalative polymerization, or melt intercalation . In addition, novel techniques have been introduced to improve filler dispersions involving the use of compatibilizers, − nanofiller surface treatments, , or the application of an electric field to clay nanocomposites. − …”

Enhanced Electrorheological Properties of PMMA–Titanium Oxide Nanocomposites

“…The authors attributed the results to different affinities between the polymers and clay. 27 Despite existing progress, numerous fundamental questions on polymer-matrix ERFs are unresolved. For instance, the magnitude and sensitivity of modulus change with respect to electric field strength remain unknown.…”

“…It is found that the PLA–clay composites are more sensitive to AC electric field, than the PP–clay composites. The authors attributed the results to different affinities between the polymers and clay . Despite existing progress, numerous fundamental questions on polymer-matrix ERFs are unresolved.…”

Characterization of Compatibilizing Effect of Organoclay in Poly(lactic acid) and Natural Rubber Blends by FT-Rheology

“…Linear rheological material functions such as storage and loss modulus ( G ′ and G ″) or complex viscosity (|η*|) from small-amplitude oscillatory shear (SAOS) tests provide internal structure and properties of polymeric materials . For example, the degree exfoliation of nanoclay can be determined by the increase in storage and loss modulus in polymer/clay nanocomposites. , The drop size reduction of immiscible polymer blends could also be related to the interfacial tension, which can be calculated by several mathematical models using G ′ and G ″ moduli. , Although many researchers have taken advantage of the linear rheological properties obtained from SAOS tests to characterize the internal structure of polymeric materials, less attention has been paid to nonlinear rheological analysis. Among several nonlinear rheological methods, nonlinear rheological properties from large-amplitude oscillatory shear (LAOS) tests have recently been of interest for characterizing complex fluids. ,,− The nonlinear shear stress response under large deformations could provide useful information regarding the topology and morphology of polymer melt systems (i.e., polymer melts, polymer composites, and polymer blends). − Salehiyan et al , investigated the relationship between morphology evaluations of PP/PS blends with various compatibilizers (organoclay and silica nanoparticles) and nonlinear rheological properties from LAOS tests and found that nonlinear rheological properties were sensitive to small changes in the internal structure of polymer blends.…”

“…20 For example, the degree exfoliation of nanoclay can be determined by the increase in storage and loss modulus in polymer/clay nanocomposites. 21,22 The drop size reduction of immiscible polymer blends could also be related to the interfacial tension, which can be calculated by several mathematical models using G′ and G″ moduli. 12,16 Although many researchers have taken advantage of the linear rheological properties obtained from SAOS tests to characterize the internal structure of polymeric materials, less attention has been paid to nonlinear rheological analysis.…”