uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
The size and synergy effects of graphene nanoplatelets andcarbon nanotubes in mechanical properties of epoxy composites.
Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
(English)Manuscript (preprint) (Other academic)
Abstract [en]

We study mechanical reinforcement in a widely used epoxy matrix with the addition of graphenenanoplatelets (GnPs) and various mixture ratios of carbon nanotubes (CNTs) withGnPs. Two different dimensions of GnPs were used with flake sizes of 5 mm and 25 mm toinvestigate the influence of nanofiller size on the composite properties. In the GnP reinforcedcomposites, the bigger flakes showed greater reinforcement at all GnP concentrations. The influenceof size on properties is significant as bigger flakes actively control the failure mechanismsin the composite. In the mixture samples, highest CNT content (9:1) showed significantimprovement in fracture toughness of 76 %. For composites with mixtures of CNTs andGnPs, the CNT:GnP ratio is an interesting factor significantly influencing the properties ofthe epoxy matrix. The combination of high aspect ratio of CNTs and larger surface area ofGnPs contribute to the synergistic effect of the CNT-GnP hybrid samples. Thermal conductivityconsistently increases with the incorporation of GnPs in the matrix. Transmission electronmicroscopy (TEM) images confirm the uniform nanofiller dispersion achieved in thecomposites with GnP. For the hybrid samples the CNTs are seen to align themselves on theGnP flakes creating an inter-connected strong nanofiller network in the matrix. The homogenousnanofiller dispersions have been achieved by high shear calendaring which is a methodcapable of being industrially scaled up.

National Category
Composite Science and Engineering
URN: urn:nbn:se:uu:diva-171572OAI: oai:DiVA.org:uu-171572DiVA: diva2:511518
Available from: 2012-03-22 Created: 2012-03-21 Last updated: 2012-04-13Bibliographically approved
In thesis
1. Structural and Physical Effects of Carbon Nanofillers in Thermoplastic and Thermosetting Polymer Systems
Open this publication in new window or tab >>Structural and Physical Effects of Carbon Nanofillers in Thermoplastic and Thermosetting Polymer Systems
2012 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Ever since the discovery of carbon nano materials like carbon nanotube (CNT) and graphene, this class of materials has gained significant attention due to their exotic properties. The principle idea of my present research project is to understand the novel improvements induced in polymer matrices with inclusion of the nanofillers. This thesis is thematically divided into three parts.

In the first part we introduce principle materials that we use for preparation of composites. Methods of nanofiller preparation and different nanocomposites as previously reported in literature are discussed to formulate the basis of our study. Different dispersion techniques are discussed which facilitate uniform nanofiller distribution. A variety of experimental methods are described which were employed to investigate the structure and properties of the composites.

In the second part we discuss in details polyamide-12 (PA12) composites using CNT and graphene as fillers. A marked improvement is recorded in the toughness of the films with incorporation of CNT, dispersed in PA12 using a surfactant. Electrical percolation is also achieved in the otherwise insulating matrix. With PA-12 fibers we explored the effect of fiber processing and CNT incorporation in the mechanical properties. Extensive wide angle x-ray diffraction was carried out to interpret the structural modifications brought about by CNT in the matrix.

The final part of the thesis deals with a thermosetting polymer, epoxy composites. CNT, Graphene and also a mixture of the two nanofillers were used as reinforcing agents. Appreciable improvement was recorded in the mechanical properties, electrical and thermal conductivity of the composites. Detailed optical and electron microscopy was carried out to get a vivid idea of the micro-structure and dispersion.

The presented work demonstrates the significant ability of carbon nanofillers to reinforce polymer matrices enhancing their mechanical, electrical and thermal properties and opening a wide horizon for a variety of applications.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2012. xiv+96 p.
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 913
Polymer, Composite, Carbon nanotube, Graphene
National Category
Composite Science and Engineering
urn:nbn:se:uu:diva-171449 (URN)978-91-554-8315-9 (ISBN)
Public defence
2012-05-04, Polhelmssalen, Ångström Laboratory, Lägerhyddsvägen 1, Uppsala, 10:15 (English)
Available from: 2012-04-11 Created: 2012-03-19 Last updated: 2012-04-19

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Chatterjee, Sanjukta
By organisation
Department of Physics and Astronomy
Composite Science and Engineering

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 468 hits
ReferencesLink to record
Permanent link

Direct link