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Preparation of Monodomain Liquid Crystal Elastomers and Liquid Crystal Elastomer Nanocomposites
Published on: February 6, 2016
The optimal structure-conductivity relation in epoxy-phthalocyanine nanocomposites.
L J Huijbregts1, H B Brom, J C M Brokken-Zijp
1Technische Universiteit Eindhoven, P.O. Box 513, 5600 MB Eindhoven, The Netherlands. L.J.Huijbregst@tue.nl
The Journal of Physical Chemistry. B
|November 17, 2006
Summary
Phthalcon-11 nanocrystals in epoxy form semiconducting materials. Despite a low percolation threshold, conductivity is limited by fractal network structures, not filler properties.
Area of Science:
- Materials Science
- Nanotechnology
- Electrical Engineering
Background:
- Phthalcon-11 (aquocyanophthalocyaninatocobalt (III)) forms semiconducting nanocrystals.
- These nanocrystals can be dispersed in epoxy coatings to create semiconducting materials.
- A low percolation threshold is desirable for efficient conductivity in composite materials.
Purpose of the Study:
- To investigate the structure-conductivity relationship in Phthalcon-11/epoxy composite coatings.
- To understand deviations from optimal conductivity realization in these materials.
- To identify pathways for enhancing the conductivity of the composite material.
Main Methods:
- Dielectric spectroscopy was used to measure the real part of electrical conductivity of Phthalcon-11/epoxy coatings and Phthalcon-11 powder as a function of frequency and temperature.
- Conducting atomic force microscopy (C-AFM) was employed to quantify local conductivity across the coating surface.
- These techniques were combined to visualize the particle network structure.
Main Results:
- A significant fraction of Phthalcon-11 crystals forms conducting channels composed of fractal building blocks.
- The observed network structure leads to conductivity levels substantially lower than the filler material itself, despite a low percolation threshold.
- The structure-conductivity relationship for the analyzed network is close to optimal.
Conclusions:
- Enhancing the conductivity of Phthalcon-11/epoxy coatings primarily requires using a filler with intrinsically higher conductivity.
- Modifying the particle network structure alone is unlikely to yield significant conductivity improvements.
- The fractal organization of nanocrystals influences the overall conductive properties of the composite material.
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