List of papers

This thesis is based on the following papers:

I Improvement of toughness and electrical properties of composites with nanotubes prepared by industrially relevant processes R Hollertz, S Chatterjee, H Gutmann, T Geiger, F A Nüesch and B T T Chu Nanotechnology, 22,125702 (2011) [1]

II Comparing carbon nanotubes and graphene nanoplatelets as reinforcements in polyamide-12 composites S Chatterjee, F A Nüesch and B T T Chu Nanotechnology, 22,275714 (2011) [2]

III Investigation of crystalline and tensile properties of carbon nanotube- filled polyamide-12 fibers melt-spun by industrially-related processes S Chatterjee, F A Reifler, B T T Chu and R Hufenus Journal for Engineered Fibers and Fabrics (accepted for publication) [3]

IV Mecahnical reinforcement and thermal conductivity in expanded graphene nanoplates reinforced epoxy composites S Chatterjee, J W Wang, W S Kuo, N H Tai, C Salzmann, W L Li, R Hollertz, F A Nüesch and B T T Chu Chemical Physics Letters 531, 6 (2012) [4]

V The size and synergy effects of graphene nanoplatelets in mechanical properties of epoxy composites S Chatterjee, F Nafezarefi, N H Tai, L Schlagenhauf, F A Nüesch and B T T Chu under preparation [5]

Reprints were made with permission from the publishers.

Preface

Preface

This doctoral thesis presents a study carried out to understand the rein- forcing effects of carbon nanofillers on the structure and physical prop- erties of thermoplastic and thermoset matrices. All the exper- iments have been performed during my tenure as a Ph.D. student be- tween 2008 - 2012 at the Swiss Federal Laboratories for Materials Science and Technology (Empa), Switzerland and the Division of Molecular and

Condensed Matter Physics at the Department of Physics and Astron- omy, Uppsala University, Sweden. Most of the activities were carried out by me with the help and support of my colleagues at three departments of Empa namely, Functional , Advanced Fibers and Protection and Physiology. In addition some experiments were done at the Materi- als Science Department of Swiss Federal Institute of Technology (ETH),

Zürich. Some of the important measurements were carried out at the synchrotrons MAX-lab, Sweden and Swiss Light Source, Switzerland.

The last four years have been a overwhelming journey for me as I have worked with many talented scientists and have enriched my knowledge with their support. In the following pages I put together the interesting

findings which have made my doctoral studies so rewarding. I take this opportunity to thank you for your interest in my research work.

v Preface

Comments on my own participation

The project has been carried out based on the framework of the pro- posal accepted by the Swiss National Science Foundation. I have per- formed most of the experimental techniques described in the thesis with adequate training and support from technical personnel. Among the five publications mentioned in this thesis I have had the main responsibility for planning and executing the experimental part and subsequent data analysis as well as writing the manuscript for four of them. For the pub- lication in which I am the second author I have carried out part of the study and have assisted the first author in manuscript preparation. I would be happy to provide further information regarding any aspect of the research mentioned in the thesis.

vi Abbreviations

List of Abbreviations

ASTM American Society for Testing and Materials CNT Carbon nanotube CVD Chemical vapour diposition DR Draw ratio DSC Differential scanning calorimetry ECI Equatorial percentage crystallinity EGNP Expanded graphene nanoplatelet Ext Extrusion factor FTIR Fourier transform infra red spectroscopy GnP Graphene nanoplatelet HPH High pressure homoginizer FDTD Finite