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A simple approach for producing high aspect ratio fluorohectorite nanoplatelets utilizing a stirred media mill (ball mill)

Published online by Cambridge University Press:  09 July 2018

M. Ziadeh ,
B. Chwalka ,
H. Kalo ,
M. R. Schütz  and
J. Breu
M. Ziadeh
Affiliation:
Lehrstuhl für Anorganische Chemie I, Universität Bayreuth, 95440 Bayreuth, Germany
B. Chwalka
Affiliation:
Lehrstuhl für Anorganische Chemie I, Universität Bayreuth, 95440 Bayreuth, Germany
H. Kalo
Affiliation:
Lehrstuhl für Anorganische Chemie I, Universität Bayreuth, 95440 Bayreuth, Germany
M. R. Schütz
Affiliation:
Lehrstuhl für Anorganische Chemie I, Universität Bayreuth, 95440 Bayreuth, Germany
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Abstract

The potential of platy nanofillers like clays in polymer nanocomposites is mostly determined by their aspect ratio. The degree of improvement that may be achieved in respect to reinforcement, gas-barrier properties and flame retardancy critically depends on the aspect ratio. Thus, increasing the aspect ratio is highly desirable in order to explore the full potential of the clay filler. Mechanical shear stress as generated in the grinding chamber of a stirred media mill (ball mill) induced an efficient exfoliation of highly hydrated and therefore ‘shear-labile’ synthetic Mg-fluorohectorite in aqueous dispersion. The attainable degree of exfoliation can be tuned and controlled through the shear forces applied by changing process parameters such as solid content and grinding media diameter. Characterization and evaluation of the exfoliation efficiency during milling was achieved by combining and cross-validating data obtained by powder X-ray diffraction (XRD), static light scattering (SLS), specific surface area measurements applying the Brunauer-Emmett-Teller (BET) equation, and scanning electron microscopy (SEM). This led to the identification of optimal processing parameters, allowing for control of the degree of exfoliation and, consequently, the aspect ratio of the nanoplatelets. Not surprisingly, besides exfoliation, increasing the magnitude of the shear stress also resulted in some reduction in platelet size.

The clay platelets obtained showed a high average aspect ratio (>600), several times greater than that of original synthetic fluorohectorite. The increase of aspect ratio was reflected in a significant enhancement of both specific surface area and cation exchange capacity (CEC) of the external basal surfaces. This method has substantial advantages compared to microfluidizer processing with respect to feasibility, batch size and particle diameter size preservation. The exfoliated nanoplatelets obtained by milling have great potential to improve mechanical properties of polymer layered silicate nanocomposites (PLSN).

Keywords

stirred media millball millhigh aspect ratiofluorohectoriteexfoliationnanoplateletspolymer nanocomposites
Type
Research Papers
Information
Clay Minerals , Volume 47 , Issue 3 , September 2012 , pp. 341 - 353
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2012

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References

Ammann, L., Bergaya, F. & Lagaly, G. (2005) Determination of the cation exchange capacity of clays with copper complexes revisited. Clay Minerals, 40, 441–453.CrossRefGoogle Scholar
Bowen, P. (2002) Particle size distribution measurement from millimeters to nanometers, and from rods to platelets. Journal of Dispersion Science and Technology, 23, 631–662.CrossRefGoogle Scholar
Burton, A.W., Ong, K., Rea, T. & Chan, I.Y. (2009) On the estimation of average crystallite size of zeolites from the Scherrer equation: A critical evaluation of its application to zeolites with one-dimensional pore systems. Microporous and Mesoporous Materials, 117, 75–90.CrossRefGoogle Scholar
Chevigny, C., Jouault, N., Dalmas, F., Boue, F. & Jestin, J. (2011) Tuning the mechanical properties in model nanocomposites: Influence of the polymer-filler interfacial interactions. Journal of Polymer Science Part B: Polymer Physics, 49, 781–791.CrossRefGoogle Scholar
Dennis, H.R., Hunter, D.L., Chang, D., Kim, S., White, J.L., Cho, J.W. & Paul, D.R. (2001) Effect of melt processing conditions on the extent of exfoliation in organoclay-based nanocomposites. Polymer, 42, 9513–9522.CrossRefGoogle Scholar
Gardolinski, J.E.F.C. & Lagaly, G. (2005) Grafted organic derivatives of kaolinite: II. Intercalation of primary n-alkylamines and delamination. Clay Minerals, 40, 547–556.CrossRefGoogle Scholar
Inam, M.A., Ouattara, S. & Frances, C. (2011) Effects of concentration of dispersions on particle sizing during production of fine particles in wet grinding process. Powder Technology, 208, 329–336.CrossRefGoogle Scholar
Kalo, H., Möller, M.W., Ziadeh, M., Dolejs, D. & Breu, J. (2010) Large scale melt synthesis in an open crucible of Na-fluorohectorite with superb charge homogeneity and particle size. Applied Clay Science, 48, 39–45.CrossRefGoogle Scholar
Kumar, A.P., Depan, D., Singh Tomer, N. & Singh, R.P. (2009) Nanoscale particles for polymer degradation and stabilization – Trends and future perspectives. Progress in Polymer Science, 34, 479–515.CrossRefGoogle Scholar
Kwade, A. (2003) A stressing model for the description and optimization of grinding processes. Chemical Engineering & Technology, 26, 199–205.CrossRefGoogle Scholar
Kwade, A. & Schwedes, J. (2007) Wet Grinding in Stirred Media Mills. Pp. 251–382. in: Handbook of Powder Technology – Particle Breakage (Salman, A.D., Ghadiri, M. & Hounslow, M.J., editors). Elsevier Science B.V., Amsterdam.Google Scholar
Meier, L.P. & Kahr, G. (1999) Determination of the cation exchange capacity (CEC) of clay minerals using the complexes of copper(II) ion with triethylenetetramine and tetraethylenepentamine. Clays and Clay Minerals, 47, 386–388.CrossRefGoogle Scholar
Mittal, V. (2008) Mechanical and gas permeation properties of compatibilized polypropylene-layered silicate nanocomposites. Journal of Applied Polymer Science, 107, 1350–1361.CrossRefGoogle Scholar
Möller, M.W., Handge, U.A., Kunz, D.A., Lunkenbein, T., Altstadt, V. & Breu, J. (2010a) Tailoring shear-stiff, mica-like nanoplatelets. ACS Nano, 4, 717–724.CrossRefGoogle ScholarPubMed
Möller, M.W., Lunkenbein, T., Kalo, H., Schieder, M., Kunz, D.A. & Breu, J. (2010b) Barrier properties of synthetic clay with a kilo-aspect ratio. Advanced Materials, 22, 5245–5249.CrossRefGoogle ScholarPubMed
Rutherford, D.W., Chiou, C.T. & Eberl, D.D. (1997) Effects of exchanged cation on the microporosity of montmorillonite. Clays and Clay Minerals, 45, 534–543.CrossRefGoogle Scholar
Scherrer, P. (1918) Bestimmung der Grösse und der inneren Struktur von Kolloidteilchen mittels Röntgenstrahlen. Nachrichten von der Gesellschaft der Wissenschaften zu Göttingen, 2, 98–100.Google Scholar
Schmidt, D., Shah, D. & Giannelis, E.P. (2002) New advances in polymer/layered silicate nanocomposites. Current Opinion in Solid State & Materials Science, 6, 205–212.CrossRefGoogle Scholar
Schütz, M.R., Kalo, H., Lunkenbein, T., Groschel, A.H., Müller, A.H.E., Wilkie, C.A. & Breu, J. (2011) Shear stiff, surface modified, mica-like nanoplatelets: a novel filler for polymer nanocomposites. Journal of Materials Chemistry, 21, 12110–12116.CrossRefGoogle Scholar
Tamura, K., Yokoyama, S., Pascua, C.S. & Yamada, H. (2008) New age of polymer nanocomposites containing dispersed high-aspect-ratio silicate nanolayers. Chemistry of Materials, 20, 2242–2246.CrossRefGoogle Scholar
Vdović, N., Jurina, I., Škapin, S.D. & Sondi, I. (2010) The surface properties of clay minerals modified by intensive dry milling – revisited. Applied Clay Science, 48, 575–580.CrossRefGoogle Scholar
Zanetti, M., Camino, G., Thomann, R. & Mülhaupt, R. (2001) Synthesis and thermal behaviour of layered silicate-EVA nanocomposites. Polymer, 42, 4501–4507.CrossRefGoogle Scholar
Zartman, G.D., Liu, H., Akdim, B., Pachter, R. & Heinz, H. (2010) Nanoscale tensile, shear, and failure properties of layered silicates as a function of cation density and stress. Journal of Physical Chemistry B, 114, 1763–1772.Google Scholar