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Controlled structure evolution of graphene networks in polymer composites
- Source :
- Chemistry of materials, 2018, Vol.30(5), pp.1524-1531 [Peer Reviewed Journal]
- Publication Year :
- 2018
- Publisher :
- American Chemical Society, 2018.
-
Abstract
- Exploiting graphene’s exceptional physical properties in polymer composites is a significant challenge because of the difficulty in controlling the graphene conformation and dispersion. Reliable processing of graphene polymer composites with uniform and consistent properties can therefore be difficult to achieve. We demonstrate distinctive regimes in morphology and nanocomposite properties, achievable through systematic control of shear rate and shear history. Remarkable changes in electrical impedance unique to composites of graphene nanoplates (GNPs) are observed. Low shear rates ≤ 0.1 s-1 break up the typical GNP agglomerates found in graphene composites, exfoliate the GNPs to fewer graphene layers and reduce orientation, enhancing electrical conductivi-ty in the composite materials. Whereas, at higher shear rates GNP orientation increases and the conductivity reduces by four orders of magnitude, as the graphene filler network is broken down. The structure of the composite continues to evolve, reflected in fur-ther changes in conductivity, after the shear force has been removed and the process temperature maintained. This work provides critical insights for understanding and controlling GNP orientation and dispersion within composites and will have important consequences in the industrial processing of graphene polymer composites via the informed design and choice of processing conditions.
- Subjects :
- Materials science
Nanocomposite
Graphene
General Chemical Engineering
Composite number
02 engineering and technology
General Chemistry
Conductivity
010402 general chemistry
021001 nanoscience & nanotechnology
01 natural sciences
0104 chemical sciences
law.invention
Shear rate
Shear (geology)
Agglomerate
Electrical resistivity and conductivity
law
Materials Chemistry
Composite material
0210 nano-technology
Subjects
Details
- Database :
- OpenAIRE
- Journal :
- Chemistry of materials, 2018, Vol.30(5), pp.1524-1531 [Peer Reviewed Journal]
- Accession number :
- edsair.doi.dedup.....c45f5a31376217fdf61b2b889bd2fef3